A Haskell library for parsing and analysing expressions - old project, written as a learning exercise when exploring Haskell, functional design patterns, category theory etc.
Expressions are represented through the Expr type - a recursive monadic structure which is a varation of the Tree monad. The monadic bind operation >>= essentially performs a variable substitution.
Expressions can be simplified, sustituted into one another, partially differentiated, and evaluated.
Build both the library and executable by running either cabal build or cabal new-build from within the directory.
Run the executable similarly, with either cabal run or cabal new-run.
Allows the user to type in a plain text function or expression. This is parsed, simplified and differentiated twice. A variable can then be subsituted for and the expressions are all further simplified.
Example output of running this executable is shown below:
λ ExpressionParser git:(main) cabal new-run
Up to date
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Input a function or expression:
f(x)=(5*x*x)-(10*x)+23
f(x) = ((5.0*(x*x))-((10.0*x)+23.0))
f'(x) = (((2.0*x)*5.0)-10.0)
f''(x) = 10.0
What would you like to substitute for x?
0.5
f(0.5) = -26.75
f'(0.5) = -5.0
f''(0.5) = 10.0
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Input a function or expression:
stop
Exiting...
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