ocisaac / my-interuptor

This repo will show me progressing through learning parsing and interrupting expressions, in C#.

I started with a bracket parsing project, and I plan to be able to eventually solve any equation (that can be simplified into a quadratic equation).

I hope you'll find my learning process intresting.

##What I've done so far

1. Parsed parens of the sort ((5)((3)(2)))

2. Parsed and calculated math expressions like 5 - 3 * 2 (with order of operations)

3. Parsed and calculated math expressions like (5 + 2) * 3 (including parens)

4. Parsed equations like 2x + 5 = 4

5. Simplfied equations

6. Solved equations (up to quadratic)

===================================================

feature	status
parse parens	DONE
parse arith	DONE
calcu arith	DONE
parse algeb	DONE
simpl algeb	DONE
solve algeb	DONE
domain	TODO
Math	TODO
library & winform	TODO

##TOOD

• Work on domain of solutions, eg. 1/x = 1/x true for all x /= 0.
• Migrate into a library and making a winform project
• Work on Math project

my-interuptor's Issues

Trying to simplify division results in a double divisoin expression.

Potential problem sources:

• Division
• Divisability checking
• Equality checking
• Multiplication

Fixing this.SimplifyDivision()

To eliminate all division there is need to add a while loop, as long as there's division in the tree, simplify it, such way will also improve performance by a little bit.

Problem with paren in ArithmeticExpression

Strings of the sort "(2+1)/(1+2)".

Reason: parens seem to be inclusing of a expression but they don't actually balance eachother/

Problem with factoring

factoring doesn't work, it is needed for canceling to work well

to cancel (x^2 + 2x + 1) with (x+1) in say, division, factoring is needed.

Fixing divisability checking

On line 212 checking for inputs such as 1/x, that are actually not divisable.

Problem with 0=x

solving for 0 = x results in plus infinity, while solving for x = 0 results in 0.

Cannot solve equations that require "smart simplifying"

e.g.: 4/(x+2) + 1 = x/(3*(x+2))

There is a need to multiply by 3(x+2), but when it does that, 4/(x+2) is not canceled.

To fix division

On line 640 add checking for reverse divisability: (x+1)/(1+x).