Need some clarification on the ** operator in Python -


i wanted start asking here this. given me part of exercise @ codeacademy.com , confused me better part of hour.

take @ following code block:

bool_one = 40 / 20 * 4 >= -4**2

now, evaluated being "8 >= 16" false.

however, codeacademy.com terminal says it's true. when started writing debug code lines, found issue in how "-4**2" gets evaluated. when run on terminal @ codeacademy on local linux system, "-4**2" in python comes out "-16"... contrary everything have learned in math classes every single calculator have run on. whether run "-4 * -4" or "-4^2" or even, using "x^y" key, "-4 [x^y] 2", still comes out "16". so, how python coming out "-16" "-4**2"?

can please clarify me?

tia.

if have -4 without parentheses, negative sign considered unary operator "multiply negative one." (-4)**2 16, because negative 4 squared, -4**2 uses normal order of operations (exponentiation before multiplication) , treats -(4**2).

hope helps!

edit: understand operator precedence, take @ handy list in docs:

http://docs.python.org/2/reference/expressions.html#operator-precedence

as can see, - has less precedence **


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