Homework, Material, and Software Manual for Math 4610
Routine Name: dxApprox
Author: Tanner Wheeler
Language: Python. This code can be run on a python 3 compiler. The file can be imported and then the method will run.
Description/Purpose: This will give a derivative approximation. The smaller the value for h the better the approximation will be.
Input: There are two inputs for this method. First, x the value of x where you would like to compute the derivative value. Second, h the smaller this value is the closer it gets to an exact approximation. If h is too small however machine precision might interpret the value as 0 and try to divide by 0. You will need to create another method with the desired function called functionToRun(x).
Output: This routine returns a decimal number of the derivative approximation. The derivative represents the slope of the given function at the given x value.
Usage/Example:
If I wanted to compute the derivative of x^2 - 3 at x = 3 with my h = 0.000000001. I would use the method set up:
dxApprox(3, 0.000000001)
This would then return the slope of x^2 -3 at x = 3 is:
6.000000496442226
Implementation/Code: The following is the code for dxApprox(x, h)
def dxApprox(x, h):
return (functionToRun(x + h) - functionToRun(x)) / h
Last Modified: September/2018