Wicked Cool Shell Scripts

#6 Validating Floating-Point Input

Upon first glance, the process of validating a floating-point (or "real") value within the confines and capabilities of a shell script might seem daunting, but consider that a floating-point number is only two integers separated by a decimal point. Couple that insight with the ability to reference a different script inline (validint), and you can see that the floating-point validation test is surprisingly short.

The Code

 #!/bin/sh # validfloat -- Tests whether a number is a valid floating-point value. # Note that this script cannot accept scientific (1.304e5) notation. # To test whether an entered value is a valid floating-point number, we # need to split the value at the decimal point. We then test the ...