Compatibility and other I/O¶
import-picard¶
Convert Picard CalculateHsMetrics per-target coverage files (.csv) to the CNVkit .cnn format.
import-seg¶
Convert a file in the SEG format (e.g. the output of standard CBS or the GenePattern server) into one or more CNVkit .cns files.
The chromosomes in a SEG file may have been converted from chromosome names to
integer IDs. Options in import-seg
can help recover the original names.
- To add a “chr” prefix, use “-p chr”.
- To convert chromosome indices 23, 24 and 25 to the names “X”, “Y” and “M” (a common convention), use “-c human”.
- To use an arbitrary mapping of indices to chromosome names, use a comma-separated “key:value” string. For example, the human convention would be: “-c 23:X,24:Y,25:M”.
export¶
Convert copy number ratio tables (.cnr files) to another format.
bed¶
The segmented output from multiple samples (*.cns
) can be exported to BED
format to support a variety of other uses, such as viewing in a genome browser.
The log2 ratio value of each segment is converted and rounded to an integer
value, as required by the BED format. To get accurate copy number values, see
the call command.
# Estimate integer copy number of each segment
cnvkit.py call Sample.cns -y -o Sample.call.cns
# Show estimated integer copy number of all regions
cnvkit.py export bed Sample.call.cns --show-neutral -y -o Sample.bed
The same format can also specify CNV regions to the FreeBayes variant caller
with FreeBayes’s --cnv-map
option:
# Show only CNV regions
cnvkit.py export bed *.call.cns -o all-samples.cnv-map.bed
Copy-number-neutral regions are not shown in the output by default, but can be
included with the --show-neutral
option.
cdt, jtv¶
A collection of probe-level copy ratio files (*.cnr
) can be exported to Java
TreeView via the standard CDT format or a plain text table:
cnvkit.py export jtv *.cnr -o Samples-JTV.txt
cnvkit.py export cdt *.cnr -o Samples.cdt
seg¶
Similarly, the segmentation files for multiple samples (*.cns
) can be
exported to the standard SEG format to be loaded in the Integrative Genomic
Viewer (IGV):
cnvkit.py export seg *.cns -o Samples.seg
nexus-basic¶
The format nexus-basic
can be loaded directly by the commercial program
Biodiscovery Nexus Copy Number, specifying the “basic” input format in that
program.