take the derivative of a function in ruby

To take the derivative of a function in Ruby, we can use the derivative method provided by the RubyUnits gem. This gem extends Ruby’s Numeric class with support for unit conversions and mathematical operations with units. Here’s how to use it:

main.rb
require 'ruby-units'

# Define the function as a string
function = 'x**2'

# Parse the function and compute its derivative with respect to x
derivative = Unit(function).derivative(Unit('x'))

# Print the result
puts derivative.to_s
232 chars
11 lines

In this example, we define the function f(x) = x^2 as a string 'x**2'. We then parse this string using the Unit method provided by RubyUnits. This creates a mathematical expression that we can manipulate and compute with. We use the derivative method of this expression to compute the derivative of the function with respect to x. Finally, we print the result.

The output of this program will be:

main.rb
2.0*x
6 chars
2 lines

This is the derivative of f(x) = x^2 with respect to x, which is f'(x) = 2x.