floating-point operations with bash

Question

how can I transform the string \"620/100\" into \"6.2\" in a bash script

The context of my question is about image processing. EXIF data are coding the focal length in f

Answer 1

bash doesn't support floating point.

You could use bc:

$ echo "50/10" | bc -l
5.00000000000000000000
$ echo "scale=1; 50/10" | bc -l
5.0