Update memory-size log message.
[lightning.git] / slicenumpy.go
index 557f0c55911d694436a29200ef1571aa62a7004e..91413824fb5d3a35234127d9e0d769b435a4ee54 100644 (file)
@@ -7,28 +7,40 @@ package lightning
 import (
        "bufio"
        "bytes"
+       "encoding/gob"
        "flag"
        "fmt"
        "io"
+       "io/ioutil"
+       "math"
        "net/http"
        _ "net/http/pprof"
        "os"
+       "regexp"
        "runtime"
+       "runtime/debug"
        "sort"
+       "strconv"
        "strings"
        "sync/atomic"
+       "unsafe"
 
        "git.arvados.org/arvados.git/sdk/go/arvados"
        "github.com/arvados/lightning/hgvs"
        "github.com/kshedden/gonpy"
-       "github.com/sirupsen/logrus"
        log "github.com/sirupsen/logrus"
        "golang.org/x/crypto/blake2b"
 )
 
 type sliceNumpy struct {
-       filter  filter
-       threads int
+       filter                filter
+       threads               int
+       chi2CaseControlColumn string
+       chi2CaseControlFile   string
+       chi2Cases             []bool
+       chi2PValue            float64
+       minCoverage           int
+       cgnames               []string
 }
 
 func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, stdout, stderr io.Writer) int {
@@ -49,7 +61,15 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
        ref := flags.String("ref", "", "reference name (if blank, choose last one that appears in input)")
        regionsFilename := flags.String("regions", "", "only output columns/annotations that intersect regions in specified bed `file`")
        expandRegions := flags.Int("expand-regions", 0, "expand specified regions by `N` base pairs on each side`")
+       mergeOutput := flags.Bool("merge-output", false, "merge output into one matrix.npy and one matrix.annotations.csv")
+       hgvsSingle := flags.Bool("single-hgvs-matrix", false, "also generate hgvs-based matrix")
+       hgvsChunked := flags.Bool("chunked-hgvs-matrix", false, "also generate hgvs-based matrix per chromosome")
+       onehotSingle := flags.Bool("single-onehot", false, "generate one-hot tile-based matrix")
+       onehotChunked := flags.Bool("chunked-onehot", false, "generate one-hot tile-based matrix per input chunk")
        flags.IntVar(&cmd.threads, "threads", 16, "number of memory-hungry assembly threads")
+       flags.StringVar(&cmd.chi2CaseControlFile, "chi2-case-control-file", "", "tsv file or directory indicating cases and controls for Χ² test (if directory, all .tsv files will be read)")
+       flags.StringVar(&cmd.chi2CaseControlColumn, "chi2-case-control-column", "", "name of case/control column in case-control files for Χ² test (value must be 0 for control, 1 for case)")
+       flags.Float64Var(&cmd.chi2PValue, "chi2-p-value", 1, "do Χ² test and omit columns with p-value above this threshold")
        cmd.filter.Flags(flags)
        err = flags.Parse(args)
        if err == flag.ErrHelp {
@@ -65,28 +85,41 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                }()
        }
 
+       if cmd.chi2PValue != 1 && (cmd.chi2CaseControlFile == "" || cmd.chi2CaseControlColumn == "") {
+               log.Errorf("cannot use provided -chi2-p-value=%f because -chi2-case-control-file= or -chi2-case-control-column= value is empty", cmd.chi2PValue)
+               return 2
+       }
+
        if !*runlocal {
                runner := arvadosContainerRunner{
                        Name:        "lightning slice-numpy",
                        Client:      arvados.NewClientFromEnv(),
                        ProjectUUID: *projectUUID,
-                       RAM:         240000000000,
-                       VCPUs:       64,
+                       RAM:         750000000000,
+                       VCPUs:       96,
                        Priority:    *priority,
                        KeepCache:   2,
                        APIAccess:   true,
                }
-               err = runner.TranslatePaths(inputDir, regionsFilename)
+               err = runner.TranslatePaths(inputDir, regionsFilename, &cmd.chi2CaseControlFile)
                if err != nil {
                        return 1
                }
                runner.Args = []string{"slice-numpy", "-local=true",
-                       "-pprof", ":6060",
-                       "-input-dir", *inputDir,
-                       "-output-dir", "/mnt/output",
-                       "-threads", fmt.Sprintf("%d", cmd.threads),
-                       "-regions", *regionsFilename,
-                       "-expand-regions", fmt.Sprintf("%d", *expandRegions),
+                       "-pprof=:6060",
+                       "-input-dir=" + *inputDir,
+                       "-output-dir=/mnt/output",
+                       "-threads=" + fmt.Sprintf("%d", cmd.threads),
+                       "-regions=" + *regionsFilename,
+                       "-expand-regions=" + fmt.Sprintf("%d", *expandRegions),
+                       "-merge-output=" + fmt.Sprintf("%v", *mergeOutput),
+                       "-single-hgvs-matrix=" + fmt.Sprintf("%v", *hgvsSingle),
+                       "-chunked-hgvs-matrix=" + fmt.Sprintf("%v", *hgvsChunked),
+                       "-single-onehot=" + fmt.Sprintf("%v", *onehotSingle),
+                       "-chunked-onehot=" + fmt.Sprintf("%v", *onehotChunked),
+                       "-chi2-case-control-file=" + cmd.chi2CaseControlFile,
+                       "-chi2-case-control-column=" + cmd.chi2CaseControlColumn,
+                       "-chi2-p-value=" + fmt.Sprintf("%f", cmd.chi2PValue),
                }
                runner.Args = append(runner.Args, cmd.filter.Args()...)
                var output string
@@ -98,7 +131,7 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                return 0
        }
 
-       infiles, err := allGobFiles(*inputDir)
+       infiles, err := allFiles(*inputDir, matchGobFile)
        if err != nil {
                return 1
        }
@@ -108,12 +141,20 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
        }
        sort.Strings(infiles)
 
-       var cgnames []string
        var refseq map[string][]tileLibRef
+       var reftiledata = make(map[tileLibRef][]byte, 11000000)
        in0, err := open(infiles[0])
        if err != nil {
                return 1
        }
+
+       matchGenome, err := regexp.Compile(cmd.filter.MatchGenome)
+       if err != nil {
+               err = fmt.Errorf("-match-genome: invalid regexp: %q", cmd.filter.MatchGenome)
+               return 1
+       }
+
+       cmd.cgnames = nil
        taglen := -1
        DecodeLibrary(in0, strings.HasSuffix(infiles[0], ".gz"), func(ent *LibraryEntry) error {
                if len(ent.TagSet) > 0 {
@@ -125,7 +166,14 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                        }
                }
                for _, cg := range ent.CompactGenomes {
-                       cgnames = append(cgnames, cg.Name)
+                       if matchGenome.MatchString(cg.Name) {
+                               cmd.cgnames = append(cmd.cgnames, cg.Name)
+                       }
+               }
+               for _, tv := range ent.TileVariants {
+                       if tv.Ref {
+                               reftiledata[tileLibRef{tv.Tag, tv.Variant}] = tv.Sequence
+                       }
                }
                return nil
        })
@@ -141,10 +189,19 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                err = fmt.Errorf("tagset not found")
                return 1
        }
-       sort.Strings(cgnames)
+       if len(cmd.cgnames) == 0 {
+               err = fmt.Errorf("no genomes found matching regexp %q", cmd.filter.MatchGenome)
+               return 1
+       }
+       sort.Strings(cmd.cgnames)
+       err = cmd.useCaseControlFiles()
+       if err != nil {
+               return 1
+       }
+       cmd.minCoverage = int(math.Ceil(cmd.filter.MinCoverage * float64(len(cmd.cgnames))))
 
        {
-               labelsFilename := *outputDir + "/labels.csv"
+               labelsFilename := *outputDir + "/samples.csv"
                log.Infof("writing labels to %s", labelsFilename)
                var f *os.File
                f, err = os.Create(labelsFilename)
@@ -152,8 +209,12 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                        return 1
                }
                defer f.Close()
-               for i, name := range cgnames {
-                       _, err = fmt.Fprintf(f, "%d,%q\n", i, trimFilenameForLabel(name))
+               for i, name := range cmd.cgnames {
+                       cc := 0
+                       if cmd.chi2Cases != nil && cmd.chi2Cases[i] {
+                               cc = 1
+                       }
+                       _, err = fmt.Fprintf(f, "%d,%q,%d\n", i, trimFilenameForLabel(name), cc)
                        if err != nil {
                                err = fmt.Errorf("write %s: %w", labelsFilename, err)
                                return 1
@@ -166,61 +227,102 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                }
        }
 
-       log.Info("building list of reference tiles to load") // TODO: more efficient if we had saved all ref tiles in slice0
+       log.Info("indexing reference tiles")
        type reftileinfo struct {
                variant  tileVariantID
                seqname  string // chr1
-               pos      int    // distance from start of chr1 to start of tile
+               pos      int    // distance from start of chromosome to starttag
                tiledata []byte // acgtggcaa...
        }
+       isdup := map[tagID]bool{}
        reftile := map[tagID]*reftileinfo{}
        for seqname, cseq := range refseq {
+               pos := 0
                for _, libref := range cseq {
-                       reftile[libref.Tag] = &reftileinfo{seqname: seqname, variant: libref.Variant}
+                       tiledata := reftiledata[libref]
+                       if len(tiledata) == 0 {
+                               err = fmt.Errorf("missing tiledata for tag %d variant %d in %s in ref", libref.Tag, libref.Variant, seqname)
+                               return 1
+                       }
+                       if isdup[libref.Tag] {
+                               log.Printf("dropping reference tile %+v from %s @ %d, tag not unique", libref, seqname, pos)
+                       } else if reftile[libref.Tag] != nil {
+                               log.Printf("dropping reference tile %+v from %s @ %d, tag not unique", tileLibRef{Tag: libref.Tag, Variant: reftile[libref.Tag].variant}, reftile[libref.Tag].seqname, reftile[libref.Tag].pos)
+                               delete(reftile, libref.Tag)
+                               log.Printf("dropping reference tile %+v from %s @ %d, tag not unique", libref, seqname, pos)
+                               isdup[libref.Tag] = true
+                       } else {
+                               reftile[libref.Tag] = &reftileinfo{
+                                       seqname:  seqname,
+                                       variant:  libref.Variant,
+                                       tiledata: tiledata,
+                                       pos:      pos,
+                               }
+                       }
+                       pos += len(tiledata) - taglen
                }
+               log.Printf("... %s done, len %d", seqname, pos+taglen)
        }
-       log.Info("loading reference tiles from all slices")
-       throttleCPU := throttle{Max: runtime.GOMAXPROCS(0)}
-       for _, infile := range infiles {
-               infile := infile
-               throttleCPU.Go(func() error {
-                       defer log.Infof("%s: done", infile)
-                       f, err := open(infile)
+
+       var mask *mask
+       if *regionsFilename != "" {
+               log.Printf("loading regions from %s", *regionsFilename)
+               mask, err = makeMask(*regionsFilename, *expandRegions)
+               if err != nil {
+                       return 1
+               }
+               log.Printf("before applying mask, len(reftile) == %d", len(reftile))
+               log.Printf("deleting reftile entries for regions outside %d intervals", mask.Len())
+               for tag, rt := range reftile {
+                       if !mask.Check(strings.TrimPrefix(rt.seqname, "chr"), rt.pos, rt.pos+len(rt.tiledata)) {
+                               delete(reftile, tag)
+                       }
+               }
+               log.Printf("after applying mask, len(reftile) == %d", len(reftile))
+       }
+
+       type hgvsColSet map[hgvs.Variant][2][]int8
+       encodeHGVS := throttle{Max: len(refseq)}
+       encodeHGVSTodo := map[string]chan hgvsColSet{}
+       tmpHGVSCols := map[string]*os.File{}
+       if *hgvsChunked {
+               for seqname := range refseq {
+                       var f *os.File
+                       f, err = os.Create(*outputDir + "/tmp." + seqname + ".gob")
                        if err != nil {
-                               return err
+                               return 1
                        }
-                       defer f.Close()
-                       return DecodeLibrary(f, strings.HasSuffix(infile, ".gz"), func(ent *LibraryEntry) error {
-                               for _, tv := range ent.TileVariants {
-                                       if dst, ok := reftile[tv.Tag]; ok && dst.variant == tv.Variant {
-                                               dst.tiledata = tv.Sequence
+                       defer os.Remove(f.Name())
+                       bufw := bufio.NewWriterSize(f, 1<<24)
+                       enc := gob.NewEncoder(bufw)
+                       tmpHGVSCols[seqname] = f
+                       todo := make(chan hgvsColSet, 128)
+                       encodeHGVSTodo[seqname] = todo
+                       encodeHGVS.Go(func() error {
+                               for colset := range todo {
+                                       err := enc.Encode(colset)
+                                       if err != nil {
+                                               encodeHGVS.Report(err)
+                                               for range todo {
+                                               }
+                                               return err
                                        }
                                }
-                               return nil
+                               return bufw.Flush()
                        })
-               })
-       }
-       if err = throttleCPU.Wait(); err != nil {
-               return 1
+               }
        }
 
-       log.Info("reconstructing reference sequences")
-       for seqname, cseq := range refseq {
-               seqname, cseq := seqname, cseq
-               throttleCPU.Go(func() error {
-                       defer log.Printf("... %s done", seqname)
-                       pos := 0
-                       for _, libref := range cseq {
-                               rt := reftile[libref.Tag]
-                               rt.pos = pos
-                               pos += len(rt.tiledata) - taglen
-                       }
-                       return nil
-               })
+       var toMerge [][]int16
+       if *mergeOutput || *hgvsSingle {
+               toMerge = make([][]int16, len(infiles))
+       }
+       var onehotIndirect [][2][]uint32 // [chunkIndex][axis][index]
+       var onehotXrefs [][]onehotXref
+       if *onehotSingle {
+               onehotIndirect = make([][2][]uint32, len(infiles))
+               onehotXrefs = make([][]onehotXref, len(infiles))
        }
-       throttleCPU.Wait()
-
-       log.Info("TODO: determining which tiles intersect given regions")
 
        throttleMem := throttle{Max: cmd.threads} // TODO: estimate using mem and data size
        throttleNumpyMem := throttle{Max: cmd.threads/2 + 1}
@@ -230,15 +332,24 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                infileIdx, infile := infileIdx, infile
                throttleMem.Go(func() error {
                        seq := make(map[tagID][]TileVariant, 50000)
-                       cgs := make(map[string]CompactGenome, len(cgnames))
+                       cgs := make(map[string]CompactGenome, len(cmd.cgnames))
                        f, err := open(infile)
                        if err != nil {
                                return err
                        }
                        defer f.Close()
-                       log.Infof("reading %s", infile)
+                       log.Infof("%04d: reading %s", infileIdx, infile)
                        err = DecodeLibrary(f, strings.HasSuffix(infile, ".gz"), func(ent *LibraryEntry) error {
                                for _, tv := range ent.TileVariants {
+                                       if tv.Ref {
+                                               continue
+                                       }
+                                       if mask != nil && reftile[tv.Tag] == nil {
+                                               // Don't waste
+                                               // time/memory on
+                                               // masked-out tiles.
+                                               continue
+                                       }
                                        variants := seq[tv.Tag]
                                        if len(variants) == 0 {
                                                variants = make([]TileVariant, 100)
@@ -250,6 +361,15 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                                        seq[tv.Tag] = variants
                                }
                                for _, cg := range ent.CompactGenomes {
+                                       if !matchGenome.MatchString(cg.Name) {
+                                               continue
+                                       }
+                                       // pad to full slice size
+                                       // to avoid out-of-bounds
+                                       // checks later
+                                       if sliceSize := 2 * int(cg.EndTag-cg.StartTag); len(cg.Variants) < sliceSize {
+                                               cg.Variants = append(cg.Variants, make([]tileVariantID, sliceSize-len(cg.Variants))...)
+                                       }
                                        cgs[cg.Name] = cg
                                }
                                return nil
@@ -257,12 +377,12 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                        if err != nil {
                                return err
                        }
-                       tagstart := cgs[cgnames[0]].StartTag
-                       tagend := cgs[cgnames[0]].EndTag
+                       tagstart := cgs[cmd.cgnames[0]].StartTag
+                       tagend := cgs[cmd.cgnames[0]].EndTag
 
                        // TODO: filters
 
-                       log.Infof("renumber/dedup variants for tags %d-%d", tagstart, tagend)
+                       log.Infof("%04d: renumber/dedup variants for tags %d-%d", infileIdx, tagstart, tagend)
                        variantRemap := make([][]tileVariantID, tagend-tagstart)
                        throttleCPU := throttle{Max: runtime.GOMAXPROCS(0)}
                        for tag, variants := range seq {
@@ -271,11 +391,19 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                                go func() {
                                        defer throttleCPU.Release()
                                        count := make(map[[blake2b.Size256]byte]int, len(variants))
+
+                                       rt := reftile[tag]
+                                       if rt != nil {
+                                               count[blake2b.Sum256(rt.tiledata)] = 0
+                                       }
+
                                        for _, cg := range cgs {
-                                               idx := (tag - tagstart) * 2
-                                               if int(idx) < len(cg.Variants) {
-                                                       count[variants[cg.Variants[idx]].Blake2b]++
-                                                       count[variants[cg.Variants[idx+1]].Blake2b]++
+                                               idx := int(tag-tagstart) * 2
+                                               for allele := 0; allele < 2; allele++ {
+                                                       v := cg.Variants[idx+allele]
+                                                       if v > 0 && len(variants[v].Sequence) > 0 {
+                                                               count[variants[v].Blake2b]++
+                                                       }
                                                }
                                        }
                                        // hash[i] will be the hash of
@@ -308,42 +436,135 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                                                remap[i] = rank[tv.Blake2b]
                                        }
                                        variantRemap[tag-tagstart] = remap
+                                       if rt != nil {
+                                               rt.variant = rank[blake2b.Sum256(rt.tiledata)]
+                                       }
                                }()
                        }
                        throttleCPU.Wait()
 
+                       var onehotChunk [][]int8
+                       var onehotXref []onehotXref
+
                        annotationsFilename := fmt.Sprintf("%s/matrix.%04d.annotations.csv", *outputDir, infileIdx)
-                       log.Infof("writing %s", annotationsFilename)
+                       log.Infof("%04d: writing %s", infileIdx, annotationsFilename)
                        annof, err := os.Create(annotationsFilename)
                        if err != nil {
                                return err
                        }
                        annow := bufio.NewWriterSize(annof, 1<<20)
-                       for tag, variants := range seq {
+                       outcol := 0
+                       for tag := tagstart; tag < tagend; tag++ {
                                rt, ok := reftile[tag]
                                if !ok {
-                                       // Reference does not use any
-                                       // variant of this tile.
-                                       // TODO: log this? mention it
-                                       // in annotations?
+                                       if mask == nil {
+                                               outcol++
+                                       }
+                                       // Excluded by specified
+                                       // regions, or reference does
+                                       // not use any variant of this
+                                       // tile. (TODO: log this?
+                                       // mention it in annotations?)
                                        continue
                                }
-                               outcol := tag - tagID(tagstart)
-                               reftilestr := strings.ToUpper(string(rt.tiledata))
                                remap := variantRemap[tag-tagstart]
+                               maxv := tileVariantID(0)
+                               for _, v := range remap {
+                                       if maxv < v {
+                                               maxv = v
+                                       }
+                               }
+                               if *onehotChunked || *onehotSingle {
+                                       onehot, xrefs := cmd.tv2homhet(cgs, maxv, remap, tag, tagstart)
+                                       onehotChunk = append(onehotChunk, onehot...)
+                                       onehotXref = append(onehotXref, xrefs...)
+                               }
+                               fmt.Fprintf(annow, "%d,%d,%d,=,%s,%d,,,\n", tag, outcol, rt.variant, rt.seqname, rt.pos)
+                               variants := seq[tag]
+                               reftilestr := strings.ToUpper(string(rt.tiledata))
+
+                               done := make([]bool, maxv+1)
+                               variantDiffs := make([][]hgvs.Variant, maxv+1)
                                for v, tv := range variants {
+                                       v := remap[v]
+                                       if v == rt.variant || done[v] {
+                                               continue
+                                       } else {
+                                               done[v] = true
+                                       }
                                        if len(tv.Sequence) < taglen || !bytes.HasSuffix(rt.tiledata, tv.Sequence[len(tv.Sequence)-taglen:]) {
+                                               fmt.Fprintf(annow, "%d,%d,%d,,%s,%d,,,\n", tag, outcol, v, rt.seqname, rt.pos)
                                                continue
                                        }
                                        if lendiff := len(rt.tiledata) - len(tv.Sequence); lendiff < -1000 || lendiff > 1000 {
+                                               fmt.Fprintf(annow, "%d,%d,%d,,%s,%d,,,\n", tag, outcol, v, rt.seqname, rt.pos)
                                                continue
                                        }
                                        diffs, _ := hgvs.Diff(reftilestr, strings.ToUpper(string(tv.Sequence)), 0)
+                                       for i := range diffs {
+                                               diffs[i].Position += rt.pos
+                                       }
                                        for _, diff := range diffs {
-                                               diff.Position += rt.pos
-                                               fmt.Fprintf(annow, "%d,%d,%d,%s:g.%s\n", tag, outcol, remap[v], rt.seqname, diff.String())
+                                               fmt.Fprintf(annow, "%d,%d,%d,%s:g.%s,%s,%d,%s,%s,%s\n", tag, outcol, v, rt.seqname, diff.String(), rt.seqname, diff.Position, diff.Ref, diff.New, diff.Left)
+                                       }
+                                       if *hgvsChunked {
+                                               variantDiffs[v] = diffs
                                        }
                                }
+                               if *hgvsChunked {
+                                       // We can now determine, for each HGVS
+                                       // variant (diff) in this reftile
+                                       // region, whether a given genome
+                                       // phase/allele (1) has the variant, (0) has
+                                       // =ref or a different variant in that
+                                       // position, or (-1) is lacking
+                                       // coverage / couldn't be diffed.
+                                       hgvsCol := hgvsColSet{}
+                                       for _, diffs := range variantDiffs {
+                                               for _, diff := range diffs {
+                                                       if _, ok := hgvsCol[diff]; ok {
+                                                               continue
+                                                       }
+                                                       hgvsCol[diff] = [2][]int8{
+                                                               make([]int8, len(cmd.cgnames)),
+                                                               make([]int8, len(cmd.cgnames)),
+                                                       }
+                                               }
+                                       }
+                                       for row, name := range cmd.cgnames {
+                                               variants := cgs[name].Variants[(tag-tagstart)*2:]
+                                               for ph := 0; ph < 2; ph++ {
+                                                       v := variants[ph]
+                                                       if int(v) >= len(remap) {
+                                                               v = 0
+                                                       } else {
+                                                               v = remap[v]
+                                                       }
+                                                       if v == rt.variant {
+                                                               // hgvsCol[*][ph][row] is already 0
+                                                       } else if len(variantDiffs[v]) == 0 {
+                                                               // lacking coverage / couldn't be diffed
+                                                               for _, col := range hgvsCol {
+                                                                       col[ph][row] = -1
+                                                               }
+                                                       } else {
+                                                               for _, diff := range variantDiffs[v] {
+                                                                       hgvsCol[diff][ph][row] = 1
+                                                               }
+                                                       }
+                                               }
+                                       }
+                                       for diff, colpair := range hgvsCol {
+                                               allele2homhet(colpair)
+                                               if !cmd.filterHGVScolpair(colpair) {
+                                                       delete(hgvsCol, diff)
+                                               }
+                                       }
+                                       if len(hgvsCol) > 0 {
+                                               encodeHGVSTodo[rt.seqname] <- hgvsCol
+                                       }
+                               }
+                               outcol++
                        }
                        err = annow.Flush()
                        if err != nil {
@@ -354,56 +575,705 @@ func (cmd *sliceNumpy) RunCommand(prog string, args []string, stdin io.Reader, s
                                return err
                        }
 
-                       throttleNumpyMem.Acquire()
-                       log.Infof("%s: preparing numpy", infile)
-                       rows := len(cgnames)
-                       cols := 2 * int(tagend-tagstart)
-                       out := make([]int16, rows*cols)
-                       for row, name := range cgnames {
-                               out := out[row*cols:]
-                               for col, v := range cgs[name].Variants {
-                                       if variants, ok := seq[tagstart+tagID(col/2)]; ok && len(variants) > int(v) && len(variants[v].Sequence) > 0 {
-                                               out[col] = int16(variantRemap[col/2][v])
-                                       } else {
-                                               out[col] = -1
+                       if *onehotChunked {
+                               // transpose onehotChunk[col][row] to numpy[row*ncols+col]
+                               rows := len(cmd.cgnames)
+                               cols := len(onehotChunk)
+                               log.Infof("%04d: preparing onehot numpy (rows=%d, cols=%d, mem=%d)", infileIdx, len(cmd.cgnames), len(onehotChunk), len(cmd.cgnames)*len(onehotChunk))
+                               throttleNumpyMem.Acquire()
+                               out := onehotcols2int8(onehotChunk)
+                               fnm := fmt.Sprintf("%s/onehot.%04d.npy", *outputDir, infileIdx)
+                               err = writeNumpyInt8(fnm, out, rows, cols)
+                               if err != nil {
+                                       return err
+                               }
+                               fnm = fmt.Sprintf("%s/onehot-columns.%04d.npy", *outputDir, infileIdx)
+                               err = writeNumpyInt32(fnm, onehotXref2int32(onehotXref), 4, len(onehotXref))
+                               if err != nil {
+                                       return err
+                               }
+                               debug.FreeOSMemory()
+                               throttleNumpyMem.Release()
+                       }
+                       if *onehotSingle {
+                               onehotIndirect[infileIdx] = onehotChunk2Indirect(onehotChunk)
+                               onehotXrefs[infileIdx] = onehotXref
+                               n := len(onehotIndirect[infileIdx][0])
+                               log.Infof("%04d: keeping onehot coordinates in memory (n=%d, mem=%d)", infileIdx, n, n*8)
+                       }
+                       if !(*onehotSingle || *onehotChunked) || *mergeOutput || *hgvsSingle {
+                               log.Infof("%04d: preparing numpy", infileIdx)
+                               throttleNumpyMem.Acquire()
+                               rows := len(cmd.cgnames)
+                               cols := 2 * outcol
+                               out := make([]int16, rows*cols)
+                               for row, name := range cmd.cgnames {
+                                       out := out[row*cols:]
+                                       outcol := 0
+                                       for col, v := range cgs[name].Variants {
+                                               tag := tagstart + tagID(col/2)
+                                               if mask != nil && reftile[tag] == nil {
+                                                       continue
+                                               }
+                                               if variants, ok := seq[tag]; ok && len(variants) > int(v) && len(variants[v].Sequence) > 0 {
+                                                       out[outcol] = int16(variantRemap[tag-tagstart][v])
+                                               } else {
+                                                       out[outcol] = -1
+                                               }
+                                               outcol++
+                                       }
+                               }
+                               seq = nil
+                               cgs = nil
+                               debug.FreeOSMemory()
+                               throttleNumpyMem.Release()
+                               if *mergeOutput || *hgvsSingle {
+                                       log.Infof("%04d: matrix fragment %d rows x %d cols", infileIdx, rows, cols)
+                                       toMerge[infileIdx] = out
+                               }
+                               if !*mergeOutput && !*onehotChunked && !*onehotSingle {
+                                       fnm := fmt.Sprintf("%s/matrix.%04d.npy", *outputDir, infileIdx)
+                                       err = writeNumpyInt16(fnm, out, rows, cols)
+                                       if err != nil {
+                                               return err
                                        }
                                }
                        }
-                       seq = nil
-                       throttleNumpyMem.Release()
+                       debug.FreeOSMemory()
+                       log.Infof("%s: done (%d/%d)", infile, int(atomic.AddInt64(&done, 1)), len(infiles))
+                       return nil
+               })
+       }
+       if err = throttleMem.Wait(); err != nil {
+               return 1
+       }
 
-                       fnm := fmt.Sprintf("%s/matrix.%04d.npy", *outputDir, infileIdx)
-                       output, err := os.Create(fnm)
+       if *hgvsChunked {
+               log.Info("flushing hgvsCols temp files")
+               for seqname := range refseq {
+                       close(encodeHGVSTodo[seqname])
+               }
+               err = encodeHGVS.Wait()
+               if err != nil {
+                       return 1
+               }
+               for seqname := range refseq {
+                       log.Infof("%s: reading hgvsCols from temp file", seqname)
+                       f := tmpHGVSCols[seqname]
+                       _, err = f.Seek(0, io.SeekStart)
                        if err != nil {
-                               return err
+                               return 1
                        }
-                       defer output.Close()
-                       bufw := bufio.NewWriterSize(output, 1<<26)
-                       npw, err := gonpy.NewWriter(nopCloser{bufw})
+                       var hgvsCols hgvsColSet
+                       dec := gob.NewDecoder(bufio.NewReaderSize(f, 1<<24))
+                       for err == nil {
+                               err = dec.Decode(&hgvsCols)
+                       }
+                       if err != io.EOF {
+                               return 1
+                       }
+                       log.Infof("%s: sorting %d hgvs variants", seqname, len(hgvsCols))
+                       variants := make([]hgvs.Variant, 0, len(hgvsCols))
+                       for v := range hgvsCols {
+                               variants = append(variants, v)
+                       }
+                       sort.Slice(variants, func(i, j int) bool {
+                               vi, vj := &variants[i], &variants[j]
+                               if vi.Position != vj.Position {
+                                       return vi.Position < vj.Position
+                               } else if vi.Ref != vj.Ref {
+                                       return vi.Ref < vj.Ref
+                               } else {
+                                       return vi.New < vj.New
+                               }
+                       })
+                       rows := len(cmd.cgnames)
+                       cols := len(variants) * 2
+                       log.Infof("%s: building hgvs matrix (rows=%d, cols=%d, mem=%d)", seqname, rows, cols, rows*cols)
+                       out := make([]int8, rows*cols)
+                       for varIdx, variant := range variants {
+                               hgvsCols := hgvsCols[variant]
+                               for row := range cmd.cgnames {
+                                       for ph := 0; ph < 2; ph++ {
+                                               out[row*cols+varIdx+ph] = hgvsCols[ph][row]
+                                       }
+                               }
+                       }
+                       err = writeNumpyInt8(fmt.Sprintf("%s/hgvs.%s.npy", *outputDir, seqname), out, rows, cols)
                        if err != nil {
-                               return err
+                               return 1
                        }
-                       log.WithFields(logrus.Fields{
-                               "filename": fnm,
-                               "rows":     rows,
-                               "cols":     cols,
-                       }).Info("writing numpy")
-                       npw.Shape = []int{rows, cols}
-                       npw.WriteInt16(out)
-                       err = bufw.Flush()
+                       out = nil
+
+                       fnm := fmt.Sprintf("%s/hgvs.%s.annotations.csv", *outputDir, seqname)
+                       log.Infof("%s: writing hgvs column labels to %s", seqname, fnm)
+                       var hgvsLabels bytes.Buffer
+                       for varIdx, variant := range variants {
+                               fmt.Fprintf(&hgvsLabels, "%d,%s:g.%s\n", varIdx, seqname, variant.String())
+                       }
+                       err = ioutil.WriteFile(fnm, hgvsLabels.Bytes(), 0666)
                        if err != nil {
-                               return err
+                               return 1
                        }
-                       err = output.Close()
+               }
+       }
+
+       if *mergeOutput || *hgvsSingle {
+               var annow *bufio.Writer
+               var annof *os.File
+               if *mergeOutput {
+                       annoFilename := fmt.Sprintf("%s/matrix.annotations.csv", *outputDir)
+                       annof, err = os.Create(annoFilename)
                        if err != nil {
-                               return err
+                               return 1
                        }
-                       log.Infof("%s: done (%d/%d)", infile, int(atomic.AddInt64(&done, 1)), len(infiles))
-                       return nil
-               })
+                       annow = bufio.NewWriterSize(annof, 1<<20)
+               }
+
+               rows := len(cmd.cgnames)
+               cols := 0
+               for _, chunk := range toMerge {
+                       cols += len(chunk) / rows
+               }
+               log.Infof("merging output matrix (rows=%d, cols=%d, mem=%d) and annotations", rows, cols, rows*cols*2)
+               var out []int16
+               if *mergeOutput {
+                       out = make([]int16, rows*cols)
+               }
+               hgvsCols := map[string][2][]int16{} // hgvs -> [[g0,g1,g2,...], [g0,g1,g2,...]] (slice of genomes for each phase)
+               startcol := 0
+               for outIdx, chunk := range toMerge {
+                       chunkcols := len(chunk) / rows
+                       if *mergeOutput {
+                               for row := 0; row < rows; row++ {
+                                       copy(out[row*cols+startcol:], chunk[row*chunkcols:(row+1)*chunkcols])
+                               }
+                       }
+                       toMerge[outIdx] = nil
+
+                       annotationsFilename := fmt.Sprintf("%s/matrix.%04d.annotations.csv", *outputDir, outIdx)
+                       log.Infof("reading %s", annotationsFilename)
+                       buf, err := os.ReadFile(annotationsFilename)
+                       if err != nil {
+                               return 1
+                       }
+                       if *mergeOutput {
+                               err = os.Remove(annotationsFilename)
+                               if err != nil {
+                                       return 1
+                               }
+                       }
+                       for _, line := range bytes.Split(buf, []byte{'\n'}) {
+                               if len(line) == 0 {
+                                       continue
+                               }
+                               fields := bytes.SplitN(line, []byte{','}, 9)
+                               tag, _ := strconv.Atoi(string(fields[0]))
+                               incol, _ := strconv.Atoi(string(fields[1]))
+                               tileVariant, _ := strconv.Atoi(string(fields[2]))
+                               hgvsID := string(fields[3])
+                               seqname := string(fields[4])
+                               pos, _ := strconv.Atoi(string(fields[5]))
+                               refseq := fields[6]
+                               if hgvsID == "" {
+                                       // Null entry for un-diffable
+                                       // tile variant
+                                       continue
+                               }
+                               if hgvsID == "=" {
+                                       // Null entry for ref tile
+                                       continue
+                               }
+                               if mask != nil && !mask.Check(strings.TrimPrefix(seqname, "chr"), pos, pos+len(refseq)) {
+                                       // The tile intersects one of
+                                       // the selected regions, but
+                                       // this particular HGVS
+                                       // variant does not.
+                                       continue
+                               }
+                               hgvsColPair := hgvsCols[hgvsID]
+                               if hgvsColPair[0] == nil {
+                                       // values in new columns start
+                                       // out as -1 ("no data yet")
+                                       // or 0 ("=ref") here, may
+                                       // change to 1 ("hgvs variant
+                                       // present") below, either on
+                                       // this line or a future line.
+                                       hgvsColPair = [2][]int16{make([]int16, len(cmd.cgnames)), make([]int16, len(cmd.cgnames))}
+                                       rt, ok := reftile[tagID(tag)]
+                                       if !ok {
+                                               err = fmt.Errorf("bug: seeing annotations for tag %d, but it has no reftile entry", tag)
+                                               return 1
+                                       }
+                                       for ph := 0; ph < 2; ph++ {
+                                               for row := 0; row < rows; row++ {
+                                                       v := chunk[row*chunkcols+incol*2+ph]
+                                                       if tileVariantID(v) == rt.variant {
+                                                               hgvsColPair[ph][row] = 0
+                                                       } else {
+                                                               hgvsColPair[ph][row] = -1
+                                                       }
+                                               }
+                                       }
+                                       hgvsCols[hgvsID] = hgvsColPair
+                                       if annow != nil {
+                                               hgvsref := hgvs.Variant{
+                                                       Position: pos,
+                                                       Ref:      string(refseq),
+                                                       New:      string(refseq),
+                                               }
+                                               fmt.Fprintf(annow, "%d,%d,%d,%s:g.%s,%s,%d,%s,%s,%s\n", tag, incol+startcol/2, rt.variant, seqname, hgvsref.String(), seqname, pos, refseq, refseq, fields[8])
+                                       }
+                               }
+                               if annow != nil {
+                                       fmt.Fprintf(annow, "%d,%d,%d,%s,%s,%d,%s,%s,%s\n", tag, incol+startcol/2, tileVariant, hgvsID, seqname, pos, refseq, fields[7], fields[8])
+                               }
+                               for ph := 0; ph < 2; ph++ {
+                                       for row := 0; row < rows; row++ {
+                                               v := chunk[row*chunkcols+incol*2+ph]
+                                               if int(v) == tileVariant {
+                                                       hgvsColPair[ph][row] = 1
+                                               }
+                                       }
+                               }
+                       }
+
+                       startcol += chunkcols
+               }
+               if *mergeOutput {
+                       err = annow.Flush()
+                       if err != nil {
+                               return 1
+                       }
+                       err = annof.Close()
+                       if err != nil {
+                               return 1
+                       }
+                       err = writeNumpyInt16(fmt.Sprintf("%s/matrix.npy", *outputDir), out, rows, cols)
+                       if err != nil {
+                               return 1
+                       }
+               }
+               out = nil
+
+               if *hgvsSingle {
+                       cols = len(hgvsCols) * 2
+                       log.Printf("building hgvs-based matrix: %d rows x %d cols", rows, cols)
+                       out = make([]int16, rows*cols)
+                       hgvsIDs := make([]string, 0, cols/2)
+                       for hgvsID := range hgvsCols {
+                               hgvsIDs = append(hgvsIDs, hgvsID)
+                       }
+                       sort.Strings(hgvsIDs)
+                       var hgvsLabels bytes.Buffer
+                       for idx, hgvsID := range hgvsIDs {
+                               fmt.Fprintf(&hgvsLabels, "%d,%s\n", idx, hgvsID)
+                               for ph := 0; ph < 2; ph++ {
+                                       hgvscol := hgvsCols[hgvsID][ph]
+                                       for row, val := range hgvscol {
+                                               out[row*cols+idx*2+ph] = val
+                                       }
+                               }
+                       }
+                       err = writeNumpyInt16(fmt.Sprintf("%s/hgvs.npy", *outputDir), out, rows, cols)
+                       if err != nil {
+                               return 1
+                       }
+
+                       fnm := fmt.Sprintf("%s/hgvs.annotations.csv", *outputDir)
+                       log.Printf("writing hgvs labels: %s", fnm)
+                       err = ioutil.WriteFile(fnm, hgvsLabels.Bytes(), 0777)
+                       if err != nil {
+                               return 1
+                       }
+               }
        }
-       if err = throttleMem.Wait(); err != nil {
-               return 1
+       if *onehotSingle {
+               nzCount := 0
+               for _, part := range onehotIndirect {
+                       nzCount += len(part[0])
+               }
+               onehot := make([]uint32, nzCount*2) // [r,r,r,...,c,c,c,...]
+               var xrefs []onehotXref
+               outcol := 0
+               for i, part := range onehotIndirect {
+                       for i := range part[1] {
+                               part[1][i] += uint32(outcol)
+                       }
+                       copy(onehot[outcol:], part[0])
+                       copy(onehot[outcol+nzCount:], part[1])
+                       outcol += len(part[0])
+                       xrefs = append(xrefs, onehotXrefs[i]...)
+
+                       part[0] = nil
+                       part[1] = nil
+                       onehotXrefs[i] = nil
+                       debug.FreeOSMemory()
+               }
+               fnm := fmt.Sprintf("%s/onehot.npy", *outputDir)
+               err = writeNumpyUint32(fnm, onehot, 2, nzCount)
+               if err != nil {
+                       return 1
+               }
+               fnm = fmt.Sprintf("%s/onehot-columns.npy", *outputDir)
+               err = writeNumpyInt32(fnm, onehotXref2int32(xrefs), 4, len(xrefs))
+               if err != nil {
+                       return 1
+               }
        }
        return 0
 }
+
+// Read case/control files, remove non-case/control entries from
+// cmd.cgnames, and build cmd.chi2Cases.
+func (cmd *sliceNumpy) useCaseControlFiles() error {
+       if cmd.chi2CaseControlFile == "" {
+               return nil
+       }
+       infiles, err := allFiles(cmd.chi2CaseControlFile, nil)
+       if err != nil {
+               return err
+       }
+       // index in cmd.cgnames => case(true) / control(false)
+       cc := map[int]bool{}
+       for _, infile := range infiles {
+               f, err := open(infile)
+               if err != nil {
+                       return err
+               }
+               buf, err := io.ReadAll(f)
+               f.Close()
+               if err != nil {
+                       return err
+               }
+               ccCol := -1
+               for _, tsv := range bytes.Split(buf, []byte{'\n'}) {
+                       if len(tsv) == 0 {
+                               continue
+                       }
+                       split := strings.Split(string(tsv), "\t")
+                       if ccCol < 0 {
+                               // header row
+                               for col, name := range split {
+                                       if name == cmd.chi2CaseControlColumn {
+                                               ccCol = col
+                                               break
+                                       }
+                               }
+                               if ccCol < 0 {
+                                       return fmt.Errorf("%s: no column named %q in header row %q", infile, cmd.chi2CaseControlColumn, tsv)
+                               }
+                               continue
+                       }
+                       if len(split) <= ccCol {
+                               continue
+                       }
+                       pattern := split[0]
+                       found := -1
+                       for i, name := range cmd.cgnames {
+                               if strings.Contains(name, pattern) {
+                                       if found >= 0 {
+                                               log.Warnf("pattern %q in %s matches multiple genome IDs (%qs, %q)", pattern, infile, cmd.cgnames[found], name)
+                                       }
+                                       found = i
+                               }
+                       }
+                       if found < 0 {
+                               log.Warnf("pattern %q in %s does not match any genome IDs", pattern, infile)
+                               continue
+                       }
+                       if split[ccCol] == "0" {
+                               cc[found] = false
+                       }
+                       if split[ccCol] == "1" {
+                               cc[found] = true
+                       }
+               }
+       }
+       allnames := cmd.cgnames
+       cmd.cgnames = nil
+       cmd.chi2Cases = nil
+       ncases := 0
+       for i, name := range allnames {
+               if cc, ok := cc[i]; ok {
+                       cmd.cgnames = append(cmd.cgnames, name)
+                       cmd.chi2Cases = append(cmd.chi2Cases, cc)
+                       if cc {
+                               ncases++
+                       }
+               }
+       }
+       log.Printf("%d cases, %d controls, %d neither (dropped)", ncases, len(cmd.cgnames)-ncases, len(allnames)-len(cmd.cgnames))
+       return nil
+}
+
+func (cmd *sliceNumpy) filterHGVScolpair(colpair [2][]int8) bool {
+       if cmd.chi2PValue >= 1 {
+               return true
+       }
+       col0 := make([]bool, 0, len(cmd.chi2Cases))
+       col1 := make([]bool, 0, len(cmd.chi2Cases))
+       cases := make([]bool, 0, len(cmd.chi2Cases))
+       for i, c := range cmd.chi2Cases {
+               if colpair[0][i] < 0 {
+                       continue
+               }
+               col0 = append(col0, colpair[0][i] != 0)
+               col1 = append(col1, colpair[1][i] != 0)
+               cases = append(cases, c)
+       }
+       return len(cases) >= cmd.minCoverage &&
+               (pvalue(col0, cases) <= cmd.chi2PValue || pvalue(col1, cases) <= cmd.chi2PValue)
+}
+
+func writeNumpyUint32(fnm string, out []uint32, rows, cols int) error {
+       output, err := os.Create(fnm)
+       if err != nil {
+               return err
+       }
+       defer output.Close()
+       bufw := bufio.NewWriterSize(output, 1<<26)
+       npw, err := gonpy.NewWriter(nopCloser{bufw})
+       if err != nil {
+               return err
+       }
+       log.WithFields(log.Fields{
+               "filename": fnm,
+               "rows":     rows,
+               "cols":     cols,
+               "bytes":    rows * cols * 4,
+       }).Infof("writing numpy: %s", fnm)
+       npw.Shape = []int{rows, cols}
+       npw.WriteUint32(out)
+       err = bufw.Flush()
+       if err != nil {
+               return err
+       }
+       return output.Close()
+}
+
+func writeNumpyInt32(fnm string, out []int32, rows, cols int) error {
+       output, err := os.Create(fnm)
+       if err != nil {
+               return err
+       }
+       defer output.Close()
+       bufw := bufio.NewWriterSize(output, 1<<26)
+       npw, err := gonpy.NewWriter(nopCloser{bufw})
+       if err != nil {
+               return err
+       }
+       log.WithFields(log.Fields{
+               "filename": fnm,
+               "rows":     rows,
+               "cols":     cols,
+               "bytes":    rows * cols * 4,
+       }).Infof("writing numpy: %s", fnm)
+       npw.Shape = []int{rows, cols}
+       npw.WriteInt32(out)
+       err = bufw.Flush()
+       if err != nil {
+               return err
+       }
+       return output.Close()
+}
+
+func writeNumpyInt16(fnm string, out []int16, rows, cols int) error {
+       output, err := os.Create(fnm)
+       if err != nil {
+               return err
+       }
+       defer output.Close()
+       bufw := bufio.NewWriterSize(output, 1<<26)
+       npw, err := gonpy.NewWriter(nopCloser{bufw})
+       if err != nil {
+               return err
+       }
+       log.WithFields(log.Fields{
+               "filename": fnm,
+               "rows":     rows,
+               "cols":     cols,
+               "bytes":    rows * cols * 2,
+       }).Infof("writing numpy: %s", fnm)
+       npw.Shape = []int{rows, cols}
+       npw.WriteInt16(out)
+       err = bufw.Flush()
+       if err != nil {
+               return err
+       }
+       return output.Close()
+}
+
+func writeNumpyInt8(fnm string, out []int8, rows, cols int) error {
+       output, err := os.Create(fnm)
+       if err != nil {
+               return err
+       }
+       defer output.Close()
+       bufw := bufio.NewWriterSize(output, 1<<26)
+       npw, err := gonpy.NewWriter(nopCloser{bufw})
+       if err != nil {
+               return err
+       }
+       log.WithFields(log.Fields{
+               "filename": fnm,
+               "rows":     rows,
+               "cols":     cols,
+               "bytes":    rows * cols,
+       }).Infof("writing numpy: %s", fnm)
+       npw.Shape = []int{rows, cols}
+       npw.WriteInt8(out)
+       err = bufw.Flush()
+       if err != nil {
+               return err
+       }
+       return output.Close()
+}
+
+func allele2homhet(colpair [2][]int8) {
+       a, b := colpair[0], colpair[1]
+       for i, av := range a {
+               bv := b[i]
+               if av < 0 || bv < 0 {
+                       // no-call
+                       a[i], b[i] = -1, -1
+               } else if av > 0 && bv > 0 {
+                       // hom
+                       a[i], b[i] = 1, 0
+               } else if av > 0 || bv > 0 {
+                       // het
+                       a[i], b[i] = 0, 1
+               } else {
+                       // ref (or a different variant in same position)
+                       // (this is a no-op) a[i], b[i] = 0, 0
+               }
+       }
+}
+
+type onehotXref struct {
+       tag     tagID
+       variant tileVariantID
+       het     bool
+       pvalue  float64
+}
+
+const onehotXrefSize = unsafe.Sizeof(onehotXref{})
+
+// Build onehot matrix (m[variant*2+isHet][genome] == 0 or 1) for all
+// variants of a single tile/tag#.
+//
+// Return nil if no tile variant passes Χ² filter.
+func (cmd *sliceNumpy) tv2homhet(cgs map[string]CompactGenome, maxv tileVariantID, remap []tileVariantID, tag, chunkstarttag tagID) ([][]int8, []onehotXref) {
+       if maxv < 2 {
+               // everyone has the most common variant
+               return nil, nil
+       }
+       tagoffset := tag - chunkstarttag
+       coverage := 0
+       for _, cg := range cgs {
+               if cg.Variants[tagoffset*2] > 0 && cg.Variants[tagoffset*2+1] > 0 {
+                       coverage++
+               }
+       }
+       if coverage < cmd.minCoverage {
+               return nil, nil
+       }
+       obs := make([][]bool, (maxv+1)*2) // 2 slices (hom + het) for each variant#
+       for i := range obs {
+               obs[i] = make([]bool, len(cmd.cgnames))
+       }
+       for cgid, name := range cmd.cgnames {
+               cgvars := cgs[name].Variants
+               for v := tileVariantID(2); v <= maxv; v++ {
+                       if remap[cgvars[tagoffset*2]] == v && remap[cgvars[tagoffset*2+1]] == v {
+                               obs[v*2][cgid] = true
+                       } else if remap[cgvars[tagoffset*2]] == v || remap[cgvars[tagoffset*2+1]] == v {
+                               obs[v*2+1][cgid] = true
+                       }
+               }
+       }
+       var onehot [][]int8
+       var xref []onehotXref
+       for homcol := 4; homcol < len(obs); homcol += 2 {
+               p := [2]float64{
+                       pvalue(obs[homcol], cmd.chi2Cases),
+                       pvalue(obs[homcol+1], cmd.chi2Cases),
+               }
+               if cmd.chi2PValue < 1 && !(p[0] < cmd.chi2PValue || p[1] < cmd.chi2PValue) {
+                       continue
+               }
+               for het := 0; het < 2; het++ {
+                       onehot = append(onehot, bool2int8(obs[homcol+het]))
+                       xref = append(xref, onehotXref{
+                               tag:     tag,
+                               variant: tileVariantID(homcol / 2),
+                               het:     het == 1,
+                               pvalue:  p[het],
+                       })
+               }
+       }
+       return onehot, xref
+}
+
+func bool2int8(in []bool) []int8 {
+       out := make([]int8, len(in))
+       for i, v := range in {
+               if v {
+                       out[i] = 1
+               }
+       }
+       return out
+}
+
+// convert a []onehotXref with length N to a numpy-style []int32
+// matrix with N columns, one row per field of onehotXref struct.
+//
+// Hom/het row contains hom=0, het=1.
+//
+// P-value row contains 1000000x actual p-value.
+func onehotXref2int32(xrefs []onehotXref) []int32 {
+       xcols := len(xrefs)
+       xdata := make([]int32, 4*xcols)
+       for i, xref := range xrefs {
+               xdata[i] = int32(xref.tag)
+               xdata[xcols+i] = int32(xref.variant)
+               if xref.het {
+                       xdata[xcols*2+i] = 1
+               }
+               xdata[xcols*3+i] = int32(xref.pvalue * 1000000)
+       }
+       return xdata
+}
+
+// transpose onehot data from in[col][row] to numpy-style
+// out[row*cols+col].
+func onehotcols2int8(in [][]int8) []int8 {
+       if len(in) == 0 {
+               return nil
+       }
+       cols := len(in)
+       rows := len(in[0])
+       out := make([]int8, rows*cols)
+       for row := 0; row < rows; row++ {
+               outrow := out[row*cols:]
+               for col, incol := range in {
+                       outrow[col] = incol[row]
+               }
+       }
+       return out
+}
+
+// Return [2][]uint32{rowIndices, colIndices} indicating which
+// elements of matrixT[c][r] have non-zero values.
+func onehotChunk2Indirect(matrixT [][]int8) [2][]uint32 {
+       var nz [2][]uint32
+       for c, col := range matrixT {
+               for r, val := range col {
+                       if val != 0 {
+                               nz[0] = append(nz[0], uint32(r))
+                               nz[1] = append(nz[1], uint32(c))
+                       }
+               }
+       }
+       return nz
+}