> #!/usr/bin/python
>
> import math
>
> print '''This program calculates the lenght of the
> hypotenuse of a right triangle
> given the lenghts of the two legs as
> parameters.\n'''
>
> leg1 = input('Enter the first leg of the triangle: ')
> leg2 = input('Enter the second leg of the triangle: ')
Hi Hoffmann,
Although this works, the use of input() is a little less safe than using
raw_input(), and input gives slightly unhappy error messages on certain
kinds of input. For example:
######
>>> input("number? ")
number? four
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<string>", line 1, in <module>
NameError: name 'four' is not defined
######
That is, certain kinds of input will give us things like NameError.
But here's another example where input() can do funny things:
######
>>> def test():
... x = input("x?: ")
... y = input("y?: ")
... print x, y
...
>>> test()
x?: 3
y?: x
3 3
######
Although this is "cute", it shows that it's also terribly hard to figure
out what's going on with input() sometimes. *grin*
So because of this, I'd recommend using raw_input() instead: even though
you have to do a little more work to get numbers out of it, it's
ultimately a bit saner and more reliable to use than input().
> def hypotenuse(x, y):
> result = math.sqrt(x**2 + y**2)
> return result
There's no need to do the assignment to 'result' here. We can return the
value straightaway:
#################################
def hypotenuse(x, y):
return math.sqrt(x**2 + y**2)
#################################
Although it's "obvious", it might also help to add some kind of
documentation string explaining hypotenuse, and what it takes in
and returns. Something like:
###################################################################
def hypotenuse(x, y):
"""hypotenuse: number number -> number
hypotenuse() returns the length of the hypotenuse of a right
triangle with legs of length x and y."""
# ... rest of function body
###################################################################
might seem like overkill for such a simple function, but the habit is a
good one.
In an ideal world, all functions would have some kind of comment like
that, to communicate the human intent to the reader. I admit that I often
just hack functions up without saying what they mean... but I do feel
guilty afterwards. *grin*
I hope this helps!
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