[Tutor] newton's sqrt formula

[Alan Gauld]

"WM." <wferguson1 at socal.rr.com> wrote

> square = input ('Please enter a number to be rooted, ')
> square = square * 1.0

Use raw_input() instead of input() and don't multiply
by 1.0 - instead convert to float using float():

square = float( raw_input ('Please enter a number to be rooted, '))

> guess = input('Please guess at the root, ')
> guess = guess * 1.0
> newguess = 0.
>
> while guess**2 != square:
>         # Newton's formula
>         newguess = guess - (guess * guess - square) / (guess * 2)
>         guess = newguess

You could just combine these two

           guess = guess - (guess * guess - square) / (guess * 2)

>         guess**2 - square

That line does not do anything!

> print
> print
> print guess, ' is the square root of ', square
> print
> print
> print 'bye'

Partly a style thing but I would prefer you either used triple
quoted strings and format chars or inserted \n characters.
ie either:

> print """


%s  is the square root of  %s



bye""" % (guess, square)

OR

print "\n\n\n",guess," is the square root of", square,"\n\n\nbye!"

Or combine both:

print "\n\n\n%s is the square root of %s\n\n\nbye!" % (guess, square)

Actually, if it was me I'd use two prints:

print "\n\n\n%s is the square root of %s" % (guess, square)
print"\n\n\nbye!"

> I offer this rewrite for your critique. Can it be terser, faster, 
> prettier?
> Thank you.

Not very critical but maybe it helps...

Alan G.