Small floats render in exponential notation

I have a WDL with command block samtools view -s ${frac} -b ${bampath} -o ${outname}.bam, where frac is a Float type.

I’m running in FireCloud. Downstream, in the PAPI script, this had turned into samtools view -s 5.0E-5 -b ...<etc>, which rather confused samtools.

Someone somewhere decided to render 0.00005 as 5.0E-5, and it wasn’t me. Can you help?

(Adam N said to reference WDL draft-2, so I am hereby doing that.)

WDL follows:

task downsample {
    File bampath
    File baipath
    File refpath
    File refipath
    Float frac
    String outname
    
    Int disk_size = ceil((size(bampath, "GB") + size(refpath, "GB") + size(refipath, "GB")) * 3)

    command {
        samtools view -s ${frac} -b ${bampath} -o ${outname}.bam
    }
    
    output {
    	File outcram = "${outname}.bam"
    }

    runtime {
        docker : "mshand/genomesinthecloud:samtools.1.8"
        disks: "local-disk ${disk_size} HDD"
        memory: "4GB"
    }
}

workflow dswf {
    call downsample
}

[pshapiro4broad]

FWIW this should workaround the issue until it’s addressed

    command {
        samtools view -s $(printf "%f" ${frac}) -b ${bampath} -o ${outname}.bam
    }

[aednichols]

https://github.com/openwdl/wdl/pull/235/files#diff-7ab1be25d3b4d9ecf4f763e14d464681R1084