dot-get_velocity_files: Generate RNA velocity files for GRanges
In BUSpaRse: kallisto | bustools R utilities

Generate RNA velocity files for GRanges

.get_velocity_files(
  gr,
  L,
  Genome,
  Transcriptome = NULL,
  out_path = ".",
  style = c("annotation", "genome", "Ensembl", "UCSC", "NCBI", "other"),
  isoform_action = c("separate", "collapse"),
  exon_option = c("full", "junction"),
  transcript_id = "transcript_id",
  gene_id = "gene_id",
  transcript_version = "transcript_version",
  gene_version = "gene_version",
  version_sep = ".",
  transcript_biotype_col = "transcript_biotype",
  gene_biotype_col = "gene_biotype",
  transcript_biotype_use = "all",
  gene_biotype_use = "all",
  chrs_only = TRUE,
  save_filtered_gtf = FALSE,
  compress_fa = FALSE,
  width = 80L
)

`gr`	A `GRanges` object for gene annotation.
`L`	Length of the biological read. For instance, 10xv1: 98 nt, 10xv2: 98 nt, 10xv3: 91 nt, Drop-seq: 50 nt. If in doubt check read length in a fastq file for biological reads with the `bash` commands: If the fastq file is gzipped, then do `zcat your_file.fastq.gz \| head` on Linux. If on Mac, then `zcat < your_file.fastq.gz \| head`. Then you will see lines with nucleotide bases. Copy one of those lines and determine its length with `str_length` in R or `echo -n <the sequence> \| wc -c` in `bash`. Which file corresponds to biological reads depends on the particular technology.
`Genome`	Either a `BSgenome` or a `XStringSet` object of genomic sequences, where the intronic sequences will be extracted from. Use `genomeStyles` to check which styles are supported for your organism of interest; supported styles can be interconverted. If the style in your genome or annotation is not supported, then the style of chromosome names in the genome and annotation should be manually set to be consistent.
`Transcriptome`	A `XStringSet`, a path to a fasta file (can be gzipped) of the transcriptome which contains sequences of spliced transcripts, or `NULL`. The transcriptome here will be concatenated with the intronic sequences to give one fasta file. When `NULL`, the transriptome sequences will be extracted from the genome given the gene annotation, so it will be guaranteed that transcript IDs in the transcriptome and in the annotation match. Otherwise, the type of transcript ID in the transcriptome must match that in the gene annotation supplied via argument `X`.
`out_path`	Directory to save the outputs written to disk. If this directory does not exist, then it will be created. Defaults to the current working directory.
`style`	Formatting of chromosome names. Use `genomeStyles` to check which styles are supported for your organism of interest and what those styles look like. This can also be a style supported for your organism different from the style used by the annotation and the genome. Then this style will be used for both the annotation and the genome. Can take the following values: annotation If style of the annnotation is different from that of the genome, then the style of the annotation will be used. genome If style of the annnotation is different from that of the genome, then the style of the genome will be used. other Custom style, need to manually ensure that the style in annotation matches that of the genome. Ensembl Or `UCSC` or `NCBI`, whichever is supported by your species of interest.
`isoform_action`	Character, indicating action to take with different transcripts of the same gene. Must be one of the following: collapse First, the union of all exons of different transcripts of a gene will be taken. Then the introns will be inferred from this union. Only the flanked intronic sequences are affected; isoforms will always be taken into account for spliced sequences or exon-exon junctions. separate Introns from different transcripts will be kept separate.
`exon_option`	Character, indicating how exonic sequences should be included in the kallisto index. Must be one of the following: full The full cDNA sequences, which include the full exonic sequences, will be used. This is the default. junction Only the exon-exon junctions, with L-1 bases on each side of the junctions, will be used.
`transcript_id`	Character vector of length 1. Tag in `attribute` field corresponding to transcript IDs. This argument must be supplied and cannot be `NA` or `NULL`. Will throw error if tag indicated in this argument does not exist.
`gene_id`	Character vector of length 1. Tag in `attribute` field corresponding to gene IDs. This argument must be supplied and cannot be `NA` or `NULL`. Note that this is different from gene symbols, which do not have to be unique. This can be Ensembl or Entrez IDs. However, if the gene symbols are in fact unique for each gene, you may supply the tag for human readable gene symbols to this argument. Will throw error if tag indicated in this argument does not exist. This is typically "gene_id" for annotations from Ensembl and "gene" for refseq.
`transcript_version`	Character vector of length 1. Tag in `attribute` field corresponding to transcript version number. If your GTF file does not include transcript version numbers, or if you do not wish to include the version number, then use `NULL` for this argument. To decide whether to include transcript version number, check whether version numbers are included in the `transcripts.txt` in the `kallisto` output directory. If that file includes version numbers, then trannscript version numbers must be included here as well. If that file does not include version numbers, then transcript version numbers must not be included here.
`gene_version`	Character vector of length 1. Tag in `attribute` field corresponding to gene version number. If your GTF file does not include gene version numbers, or if you do not wish to include the version number, then use `NULL` for this argument. Unlike transcript version number, it's up to you whether to include gene version number.
`version_sep`	Character to separate bewteen the main ID and the version number. Defaults to ".", as in Ensembl.
`transcript_biotype_col`	Character vector of length 1. Tag in `attribute` field corresponding to transcript biotype.
`gene_biotype_col`	Character vector of length 1. Tag in `attribute` field corresponding to gene biotype.
`transcript_biotype_use`	Character, can be "all" or a vector of transcript biotypes to be used. Transcript biotypes aren't entirely the same as gene biotypes. For instance, in Ensembl annotation, `retained_intron` is a transcript biotype, but not a gene biotype. If "cellranger", then a warning will be given. See `data("ensembl_tx_biotypes")` for all available transcript biotypes from Ensembl.
`gene_biotype_use`	Character, can be "all", "cellranger", or a vector of gene biotypes to be used. If "cellranger", then the biotypes used by Cell Ranger's reference are used. See `data("cellranger_biotypes")` for gene biotypes the Cell Ranger reference uses. See `data("ensembl_gene_biotypes")` for all available gene biotypes from Ensembl. Note that gene biotypes and transcript biotypes are not always the same.
`chrs_only`	Logical, whether to include chromosomes only, for GTF and GFF files can contain annotations for scaffolds, which are not incorporated into chromosomes. This will also exclude haplotypes. Defaults to `TRUE`. Only applicable to species found in `genomeStyles()`.
`save_filtered_gtf`	Logical. If filtering type, biotypes, and/or chromosomes, whether to save the filtered `GRanges` as a GTF file.
`compress_fa`	Logical, whether to compress the output fasta file. If `TRUE`, then the fasta file will be gzipped.
`width`	Maximum number of letters per line of sequence in the output fasta file. Must be an integer.