How can I compare two floating point numbers in Bash?

More conveniently

This can be done more conveniently using Bash’s numeric context:

if (( $(echo "$num1 > $num2" |bc -l) )); then


Piping through the basic calculator command bc returns either 1 or 0.

The option -l is equivalent to --mathlib; it loads the standard math library.

Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or false.

Please, ensure that the bc basic calculator package is installed.

Caveat: Exponential notation should be written as *10^; not E, nor e.

For example:

$ echo "1*10^3==1000" |bc


$ echo "1E3==1000" |bc

Strategies to overcome this bc limitation are discussed here.

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