Hi, I am trying to convert some VCFs to GDS and convert them back, but had some errors. Could you please get me some suggestions? Thanks a lot!

library(SeqArray)
library(VariantAnnotation)

## both vcfs have 5 metadata columns
vcf1 <- readVcf('sample1.vcf','hg38')
vcf1
# class: CollapsedVCF
# dim: 950 1
# rowRanges(vcf):
#   GRanges with 5 metadata columns: paramRangeID, REF, ALT, QUAL, FILTER

vcf2 <- readVcf('sample2.vcf','hg38')
vcf2
# class: CollapsedVCF
# dim: 950 1
# rowRanges(vcf):
#   GRanges with 5 metadata columns: paramRangeID, REF, ALT, QUAL, FILTER

## convert to gds
seqVCF2GDS("sample1.vcf", "sample1.gds", storage.option="ZIP_RA")
seqVCF2GDS("sample2.vcf", "sample2.gds", storage.option="ZIP_RA")

## after converting, can not convert back to vcf
gds1 <- seqOpen("sample1.gds")
seqAsVCF(gds1)
# Error in dimnames(v) <- listsample.id, variant.id) :
#   length of 'dimnames' [1] not equal to array extent

gds2 <- seqOpen("sample2.gds")
seqAsVCF(gds2)
# Error in dimnames(v) <- listsample.id, variant.id) :
#   length of 'dimnames' [1] not equal to array extent

## can somehow get around this problem by subsetting info and fmt, but now the rowRanges have duplicated metadata columns
seqExport(gds1, "slim_sample1.gds", info.var=c("SVTYPE","SVLEN","END"), fmt.var=c("DP","GQ","AO","AP"))
seqClose(gds1)
slim1 <- seqOpen("slim_sample1.gds")
seqAsVCF(slim1)
# class: CollapsedVCF
# dim: 950 1
# rowRanges(vcf):
#   GRanges with 9 metadata columns: ID, REF, ALT, QUAL, FILTER, REF, ALT, QUAL, FILTER

seqExport(gds2, "slim_sample2.gds", info.var=c("SVTYPE","SVLEN","END"), fmt.var=c("DP","GQ","AO","AP"))
seqClose(gds2)
slim2 <- seqOpen("slim_sample2.gds")
seqAsVCF(slim2)
# class: CollapsedVCF
# dim: 950 1
# rowRanges(vcf):
#   GRanges with 9 metadata columns: ID, REF, ALT, QUAL, FILTER, REF, ALT, QUAL, FILTER
seqClose(slim1)
seqClose(slim2)

## can merge the two gds, but can not convert the merged to vcf
seqMerge(c("slim_sample1.gds", "slim_sample2.gds"), "merged.gds", storage.option="ZIP_RA")
merged <- seqOpen("merged.gds")
seqAsVCF(merged)
# Error in .Call2("solve_user_SEW0", start, end, width, PACKAGE = "IRanges") :
#   solving row 1: range cannot be determined from the supplied arguments (too many NAs)

sessionInfo()
# R version 3.4.3 (2017-11-30)
# Platform: x86_64-pc-linux-gnu (64-bit)
# Running under: Red Hat Enterprise Linux Server release 6.6 (Santiago)

# Matrix products: default
# BLAS: /gnet/is2/p01/apps/R/3.4.3-20171201-stablerc/x86_64-linux-2.6-rhel6/lib64/R/lib/libRblas.so
# LAPACK: /gnet/is2/p01/apps/R/3.4.3-20171201-stablerc/x86_64-linux-2.6-rhel6/lib64/R/lib/libRlapack.so

# locale:
#  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
#  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8
#  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8
#  [7] LC_PAPER=en_US.UTF-8       LC_NAME=C
#  [9] LC_ADDRESS=C               LC_TELEPHONE=C
# [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C

# attached base packages:
# [1] stats4    parallel  stats     graphics  grDevices utils     datasets
# [8] methods   base

# other attached packages:
#  [1] SeqArray_1.18.2            gdsfmt_1.14.1
#  [3] VariantAnnotation_1.24.5   Rsamtools_1.30.0
#  [5] Biostrings_2.46.0          XVector_0.18.0
#  [7] SummarizedExperiment_1.8.1 DelayedArray_0.4.1
#  [9] matrixStats_0.53.0         Biobase_2.38.0
# [11] GenomicRanges_1.30.1       GenomeInfoDb_1.14.0
# [13] IRanges_2.12.0             S4Vectors_0.16.0
# [15] BiocGenerics_0.24.0

SeqArray_1.22.6 fixes the bug in the merged GDS file:

merged <- seqOpen("merged.gds") seqAsVCF(merged) "Error in .Call2("solveuserSEW0", start, end, width, PACKAGE = "IRanges") : solving row 1: range cannot be determined from the supplied arguments (too many NAs)"