**Symbolic** math for Ruby

## Installation

gem install symbolic

## Introduction

This gem can help you:

- if you want to get a simplified form of a big equation;
- if you want to speed up similar calculations;
- if you need an abstraction layer for math.

Symbolic doesn’t have any external dependencies. It uses only pure ruby (less than 400 lines of code).

## Tutorial

First, you need to create a symbolic variable.

x = var # you can set a name of variable # (useful if you print equations) angle = var :name => 'θ' # or starting value pi = var :value => 3.14 # or bind its value to a proc y = var { x ** 2 } # you can set a value for already created variable x.value = 3

Now, you can do any math operations with it.

```
f = 2*x + 1
puts f # => 2*x+1
```

To get value of symbolic expression you just call value:

```
f.value # => 7
```

If symbolic expression contains variables without value then it returns nil.

```
z = var
(z+1).value # => nil
```

All symbolic expression are automatically simplified when created:

0 * x # => 0 2 + x + 1 # => x + 3 -(x-y) + 2*x # => x + y (x**2)**3 / x # => x**5 # etc. (more examples can be found in symbolic_spec.rb)

If you need to use a function from Math module with symbolic variable, use Symbolic::Math module.

```
cos = Symbolic::Math.cos(x)
x.value = 0
cos.value # => 1.0
```

You can get a list of variables from symbolic expression:

```
(x+y+1).variables # => [x, y]
```

So you can get a list of variables without value:

(x+y+1).variables.select {|var| var.value.nil? }

You can get an information about number of different operations used in a symbolic expression:

```
f = (2*x-y+2)*x-2**(x*y)
f.operations # => {"+"=>1, "-"=>2, "*"=>3, "/"=>0,
# "**"=>1, "-@"=>0}
```

## TODO

- a lot of refactoring (code is pretty messy at this stage);
- plotting capabilities;
- derivatives;
- integrals;
- thorough documentation.

## Author

I am ready to help with any questions related to Symbolic. I welcome any contribution.