My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Reply
 
LinkBack Thread Tools Display Modes
September 7th, 2015, 01:41 PM   #1
Senior Member
 
Mr Davis 97's Avatar
 
Joined: Feb 2014
From: Louisiana

Posts: 156
Thanks: 6

Math Focus: algebra and the calculus
What does the term "pointwise" refer to?

In reading mathematical texts (especially on functions), I come across the term "pointwise". There seems to be a paucity of information explaining it on the internet, so I turn to the forum for an intuitive explanation. The context is when the term is used as in "pointwise addition" or "pointwise multiplication" of functions.
Mr Davis 97 is offline  
 
September 7th, 2015, 02:14 PM   #2
Global Moderator
 
Joined: May 2007

Posts: 6,641
Thanks: 625

See answer in physics forums.
mathman is offline  
September 7th, 2015, 04:20 PM   #3
Math Team
 
Joined: Jan 2015
From: Alabama

Posts: 3,261
Thanks: 894

You should give a link so the rest of us can find it!
https://www.physicsforums.com/threads/what-does-the-term-pointwise-refer-to.831356/

Last edited by skipjack; September 8th, 2015 at 05:49 PM.
Country Boy is offline  
September 7th, 2015, 09:27 PM   #4
Global Moderator
 
Joined: Dec 2006

Posts: 19,952
Thanks: 1842

In the specified context, the word "pointwise" is redundant.
skipjack is offline  
September 8th, 2015, 02:24 AM   #5
Senior Member
 
Joined: Apr 2014
From: Glasgow

Posts: 2,132
Thanks: 717

Math Focus: Physics, mathematical modelling, numerical and computational solutions
I haven't encountered "point-wise" much, but I have encountered "piece-wise". I think point-wise makes sense once you've read about piece-wise things
Benit13 is offline  
September 8th, 2015, 05:09 PM   #6
Global Moderator
 
Joined: May 2007

Posts: 6,641
Thanks: 625

I apologize for leaving out reference. To repeat - let f and g be functions, then pointwise addition f+g means f(x)+g(x) for every x in the domain. I also added a comment that the concept of pointwise is used more ofter in the context of taking limits.

$\displaystyle f_n-> f\ pointwise,\ means \ f_n(x)->f(x) \ for\ each\ x$.

There are many other kinds of convergence, so it is important to state what one means in context.
mathman is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
pointwise, refer, term



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
A "simple" application of dirac delta "shift theorem"...help SedaKhold Calculus 0 February 13th, 2012 12:45 PM
"separate and integrate" or "Orangutang method" The Chaz Calculus 1 August 5th, 2011 10:03 PM
sample exeriment-need help finding "statistic" and "result" katie0127 Advanced Statistics 0 December 3rd, 2008 02:54 PM
terms "non-increasing" or "non-decreasing" Ujjwal Number Theory 2 September 29th, 2008 08:06 AM
History of the term "trace" for intersection of su mrcamalot Real Analysis 1 March 8th, 2008 05:29 PM





Copyright © 2018 My Math Forum. All rights reserved.