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

bash handles only integer maths but you can use bc command as follows:

$ num1=3.17648E-22
$ num2=1.5
$ echo $num1'>'$num2 | bc -l
0
$ echo $num2'>'$num1 | bc -l
1

Note that exponent sign must be uppercase