How to compare two floating point numbers in Bash?

Question

I am trying hard to compare two floating point numbers within a bash script. I have to variables, e.g.

let num1=3.17648e-22
let num2=1.5

No

Answer 1

Pure bash solution for comparing floats without exponential notation, leading or trailing zeros:

if [ ${FOO%.*} -eq ${BAR%.*} ] && [ ${FOO#*.} \> ${BAR#*.} ] || [ ${FOO%.*} -gt ${BAR%.*} ]; then
  echo "${FOO} > ${BAR}";
else
  echo "${FOO} <= ${BAR}";
fi

Order of logical operators matters. Integer parts are compared as numbers and fractional parts are intentionally compared as strings. Variables are split into integer and fractional parts using this method.

Won't compare floats with integers (without dot).