parralelizing a part of a script shell

Question

#!/bin/bash
for tracelength in 10 20 50 100 ; do
    step=0.1
    short=0
    long=1
    for firstloop in {1..10}; do
        ratio=0
        for secondloop in {1..10} ; do
            for repeat in {1..20} ; do
               echo $tracelength $short $long $ratio >results.csv
               python3 main.py "$tracelength" "$short" "$long" "$ratio" > file.smt2                     
               /usr/bin/time /Users/Desktop/optimathsat-1.5.1-macos-64-bit/bin/optimathsat < file.smt2 > results.csv
            done
            ratio=$(echo "scale=10; $ratio + $step" | bc)
        done
        short=$(echo "scale=10; $short + $step" | bc)
        long=$(echo "scale=10; $long - $step" | bc)
    done
done

I want to parallelize the inside loop (repeat).

I have installed GNU parallel and I know some of the basics but because the loop has more than one command I have no idea how I can parallelize them.

I transfered the content of the loop to another script which I guess is the way to go but my 3 commands need to take the variables (tracelength, ratio, short, long) and run according to them. any idea how to pass the parameters from a script to a subscript. or do you maybe have a better idea of parallelization?

I am editing the question because I used the answer below but the now my execution time is always 0.00 regadless of how big file.smt2 is.

this is the new version of code:

 #!/bin/bash
    doone() {
        tracelength="$1"
        short="$2"
        long="$3"
        ratio="$4"
        #echo "$tracelength $short $long $ratio" >> results.csv
        python3 main.py "$tracelength" "$short" "$long" "$ratio" >> file.smt2
        gtime -f "%U" /Users/Desktop/optimathsat-1.5.1-macos-64-bit/bin/optimathsat < file.smt2
    }
    export -f doone
    step=0.2
    parallel doone \
             ::: 200 300 \
             :::: <(seq 0 $step 0.5) \
             ::::+ <(seq 1 -$step 0.5) \
             :::: <(seq 0 $step 0.5) \
             ::: {1..5} &> results.csv

Answer 1

In your original code you overwrite results.csv again and again. I assume that is a mistake and that you instead want it combined into a big csvfile:

doone() {
    tracelength="$1"
    short="$2"
    long="$3"
    ratio="$4"
    echo "$tracelength $short $long $ratio"
    python3 main.py "$tracelength" "$short" "$long" "$ratio" |
        /usr/bin/time /Users/Desktop/optimathsat-1.5.1-macos-64-bit/bin/optimathsat
}
export -f doone
step=0.1
parallel doone \
         ::: 10 20 50 100 \
         :::: <(seq 0 $step 0.9) \
         ::::+ <(seq 1 -$step 0.1) \
         :::: <(seq 0 $step 0.9) \
         ::: {1..20} > results.csv

If you want a csvfile per run:

parallel --results outputdir/ doone \
         ::: 10 20 50 100 \
         :::: <(seq 0 $step 0.9) \
         ::::+ <(seq 1 -$step 0.1) \
         :::: <(seq 0 $step 0.9) \
         ::: {1..20}

If you want a csv file containing the arguments and run time use:

parallel --results output.csv doone \
         ::: 10 20 50 100 \
         :::: <(seq 0 $step 0.9) \
         ::::+ <(seq 1 -$step 0.1) \
         :::: <(seq 0 $step 0.9) \
         ::: {1..20}