Differentiate

Differentiate any algebraic expression

This is something I wrote while learning functional programming in Haskell. I had already written something similar in objected-oriented Python, and I learned a lot from rewriting it in a purely functional way.

Supported functions: sin, cos, tan, sec, log, exp, sqrt

The book I used to learn Haskell - Learn You a Haskell for Great Good

The parser is written using Parsec - Parsec

How to run

ghc --make differentiate.hs
./differentiate

Notes

• Use ~ instead of - for unary minus.
• Integers are not supported yet, use float instaed : 2.0 instead of 2.
• Brackets have to be used in some places to get the expression parsed correctly, specifically, while writing unary expressions.

Examples

$ ./differentiate
Expression in terms of x? (Note: Use ~ for unary minus)
sin(cos(x))
Parsed as: (sin(cos('x')))
Result: ((cos(cos('x'))) * (-(sin('x'))))

$ ./differentiate
Expression in terms of x? (Note: Use ~ for unary minus)
sin(x)*(cos(x)-(tan(x)))
Parsed as: ((sin('x')) * ((cos('x')) - (tan('x'))))
Result: (((sin('x')) * ((-(sin('x'))) - ((sec('x')) ^ (2.0)))) + ((cos('x')) * ((cos('x')) - (tan('x')))))