bc Calculator

felipeabrao

Hello, everybody!

I have used the bc calculator, but I get the following message when I try to perform 2^1.5:

Runtime warning (func=(main), adr=9): non-zero scale in exponent

How could I fix it up?

Thank you in advance!

raohenry

Hey @felipeabrao, welcome!

The bc calculator only supports integer exponents by default. That’s why 2^1.5 throws the non-zero scale in exponent warning—it can’t handle fractional powers like 1.5.

To work around this, you can use bc with the math library (-l flag) and rewrite the expression using logarithms and exponentials. Here's how:

echo "e(1.5 * l(2))" | bc -l

This computes 2^1.5 using the identity:
x^y = e(y * ln(x))

Let me know if you want to keep using bc for more complex math or switch to something like awk or Python for better floating-point support.

Cheers!