On May 8, 6:14 pm, Luis Zarrabeitia <[EMAIL PROTECTED]> wrote: > On Thursday 08 May 2008 06:54:42 pm [EMAIL PROTECTED] wrote: > > > The problem is that Python parses -123**0 as -(123**0), not as > > (-123)**0. > > Actually, I've always written it as (-123)**0. At least where I'm from, > exponentiation takes precedence even over unary "-". (to get a power of -123, > you must write $(-123)^0$ [latex])
FWIW, my TI-89 evaluates it as -1. > Though not an authoritative source, wikipedia also uses the (-x)^y > notation:http://en.wikipedia.org/wiki/Exponentiation#Powers_of_minus_one > > Btw, there seems to be a math problem in python with exponentiation... > > >>> 0**0 > > 1 > > That 0^0 should be a nan or exception, I guess, but not 1. > > [just found out while trying the poster's example] Technically correct, but 0**0 == 1 is actually pretty useful. For one thing, it lets you create a Vandermonde matrix without making 0 a special case. -- http://mail.python.org/mailman/listinfo/python-list
