[Python-ideas] Consider adding clip or clamp function to math

[Stephen J. Turnbull]

Steven D'Aprano writes:

 > > clamp(x, y, z) --> NaN if z < y
 > 
 > That's a clear error, and it should raise immediately. I see no 
 > advantage to returning NAN in this case.
 > 
 > Think about why you're clamping. It's unlikely to be used just once, for 
 > a single calculation. You're likely to be clamping a whole series of 
 > values, with a fixed lower and upper bounds.

"Likely" isn't a good enough reason:

    x = [clamp(x[t], f(t), g(t)) for t in range(1_000_000)]

is perfectly plausible code.  The "for which case is it easier to
write a wrapper" argument applies here, I think.