Solved

algorithm to calculate the derivative

Posted on 1997-04-09
2
716 Views
Last Modified: 2011-09-20
I am looking for an algorithm to calculate the derivative of functions like i=f(v). Do you know if this is somewhere publicly awailable?
0
Comment
Question by:ericj040697
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
2 Comments
 

Accepted Solution

by:
Msoft earned 50 total points
ID: 1249868
Hi,

There are Mathematics ways to calculate the derivative of GOOD functions.  (like Sin , Cos , tan, log  etc.)
In this way you can calculate the derivative Exactly. ( Here I mean Exactly as Math. Exactly )
For Ex.  Sin(a)` = Cos (a) ,  Cos(a)` = -Sin (a) etc. (There only About 20 Formulas)

But If you have not GOOD (Normal) Function so you can't calculate the derivative Exactly.
And You have only Approximately  Methods.  (From Array of Variables and not from Function )

Physics Ex:

We know velocity of  Car In Each  Second. And we want to Calculate the Acceleration in Each Sec.

Time: (Sec)           0          1         ....i ...        n
Velocity:(M/s)      V(0)   V(1)    ...V(I).. V(n)            (In array V: Element  V(i) it`s Velocity at Sec i )

SR: Sampling Rate ( In Our Example is Each Sec =>  SR = 1 )
The A(i)  - acceleration at momet i (at Sec i ) equal to V` (derivative of V)

A(i) = V` = ( V(i)-V(i-1) ) / SR


I Hope It`s will help you.
                                           



0
 
LVL 4

Expert Comment

by:jos010697
ID: 1249869
You're basiscally correct; a better estimation of f'(x), given
f(x) (in any form), is

   (f(x+h)-f(x-h))/(2h)

kind regards,

Jos
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This tutorial is posted by Aaron Wojnowski, administrator at SDKExpert.net.  To view more iPhone tutorials, visit www.sdkexpert.net. This is a very simple tutorial on finding the user's current location easily. In this tutorial, you will learn ho…
Summary: This tutorial covers some basics of pointer, pointer arithmetic and function pointer. What is a pointer: A pointer is a variable which holds an address. This address might be address of another variable/address of devices/address of fu…
The goal of this video is to provide viewers with basic examples to understand and use structures in the C programming language.
Video by: Grant
The goal of this video is to provide viewers with basic examples to understand and use nested-loops in the C programming language.

632 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question