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if statement - Floating point comparison with variable in bash


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Bash can't handle floats. Pipe to bc instead:

if [ $(echo " $test > $k" | bc) -eq 1 ]

The error you see though is because the test command (i.e. the [) needs spaces before and after

It is even better to use (( ... )) since you compare numbers like this:

if (( $(bc <<< "$test > $k") ))

The part in the loop should look like this:

if (( $(bc <<< "$test <= 1") ))
then
    echo "output"
elif (( $(bc <<< "$test > $k") ))
then
    echo "output$k"
fi

Relational expressions evaluate to 0, if the relation is false, and 1 if the relation is true [source]. Note however that is a behavior of GNU bc, and it is not POSIX compiant.


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