Global variables in functions

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I have been trying to use global variables so I can make changes to the said variable in different functions but I can't seem to do it. It seems like the second function does not work. Please help.
function one=new1()
clc
clear global
global m
m=0;
disp('soup')
function hamburger=eat()
m=m+1
disp('sandwich')

Accepted Answer

Image Analyst
Image Analyst on 11 Sep 2017
Edited: Image Analyst on 11 Sep 2017
Get rid of the "clear global" function in new1(), which blew away your existing globals, and add "global m" to eat():
function one=new1()
global m
clc
m=0;
disp('soup')
function hamburger=eat()
global m
m=m+1
disp('sandwich')
And the variables are only global for the functions that actually have the "global m" line in them, not to other functions that don't have that line.
  3 Comments
Image Analyst
Image Analyst on 11 Sep 2017
It must not be getting called. Set a breakpoint inside eat() and start your program. See if it stops there. It probably doesn't which means that eat() never gets called. Step through your program from earlier to see what lines of code get executed and try to figure out where you're calling it and why program execution never reaches that line of code.

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More Answers (2)

dpb
dpb on 11 Sep 2017
>> help clear
...
| clear GLOBAL removes all global variables.
...
However, using global is not recommended as a general programming practice; you don't show enough context to see why there's any reason should be using one here so I'd suggest not doing so.

Raja Awais Liaqait
Raja Awais Liaqait on 7 Oct 2019
I want help in the following code.
global min_realvar ;
global max_realvar ;
Firstly, I want to get the value of these variables and secondly i want to write them in such away that I can give the values of these variables as an input.
  1 Comment
Image Analyst
Image Analyst on 7 Oct 2019
You already HAVE them since you put the global line in your workspace. No need to do anything more. Get them into another variable by referencing them.
someOtherVariable = min_realvar * 500 + 123424; % Whatever....
If you want, you can just pass them in as variables in the input argument list. Or you can write them to a disk file and pass the filename.

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