Complete Algebraic Equations

Question

Im trying to build an app that graphs an equation based on user input. The equation would be in slope intercept form: y = mx + b, for m as slope and b as y intercept. However, this isn't working for me in python!

I tried this:

>>> x = 3
>>> 1/2x

and was returned this:

  File "<stdin>", line 1
    1/2x
       ^
SyntaxError: invalid syntax
>>>

How would I make it so that this returns 1.5?

Can you ask them to input the slope and intercept separately? That would simplify the logic for pulling that data out of the equation considerably. — Swagin9, Sep 07 '16 at 15:14
Technically, yes, but I wanted to make it very simple by just having them enter the equation — doejs, Sep 07 '16 at 15:28
can user input equation with parenthesis like `(1/2)x+(3/5)` or without parenthesis `1/2x+3/5` ? — Kalpesh Dusane, Sep 07 '16 at 15:54

corn3lius · Answer 1 · 2016-09-07T16:34:00.733

0

import re
mxb = re.compile('''(?P<slope>[(\d)/.]*)x\s+(?P<sign>[+-])\s+(?P<intercept>[\d./]*)''')
s = '1/2x + 5' 
match = mxb.match(s)
if match : 
    print( match.groupdict() )

test the python regex here : pythex.org

edited Sep 07 '16 at 16:34

answered Sep 07 '16 at 15:04

corn3lius

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The goal is to solve it as is. The user needs to be able to enter the equation of the line. – doejs Sep 07 '16 at 15:06

Complete Algebraic Equations

1 Answers1