# Output variable of a function as an input of another function - Problem

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Christos Tsallis on 25 Mar 2021
Commented: Christos Tsallis on 25 Mar 2021
Hello,
I got two ".m" files, the first one is called "Ex_1" and the second one is called "Ex_2" as shown bellow. Output of Ex_1 must be the Input of Ex_2. How can I make function Ex_2 understand the values of a, b? Is there anyway to call variable a and b from Ex_1 in Ex_2? Thanks for your time, appreciate your help!
function [a,b]=Ex_1(dat) %dat is just a variable which I load in my program
x=log10(dat(:,1));
y=dat(:,2);
P=size(dat,1);
SSxy=sum(x.*y)-(sum(x)*sum(y)/P);
SSxx=sum(x.^2)-((sum(x))^2/P);
a=SSxy/SSxx
y_bar=sum(y)/P;
x_bar=sum(x)/P;
b=y_bar-a*x_bar
end
function [freq]=Ex_2(a,b,db) %a, b is the same a, b of function Ex_1. db value doesn't matter
freq=(db-b)/a;
end
##### 2 CommentsShowHide 1 older comment
Christos Tsallis on 25 Mar 2021
After I run Ex_1, I am typing Ex_2(a,b,0) and I am expecting the program to understand that a, b are the same values of Ex_1 (db=0 for this example). The problem is that I got an error of unrecognized function of variable 'a' that's why I am asking. I am trying to understand how functions call each other thats why I am using 2 functions.

drummer on 25 Mar 2021
Did you do a third procedural script calling both of them?
You could do like this in your third script.m:
[a, b] = Ex_1(data);
%% % by doing this break, you can check if a and b were loaded into your workspace
% once they were loaded, you can now call your second script by
[freq] = Ex_2(a, b, db); % assuming you´re loading db variable mannualy.
This is not necessarily the only thing you could do. You could also type these lines in your command window.
Christos Tsallis on 25 Mar 2021
Thanks for your help ! I am new to programming and I am facing problems with simple things.

R2020b

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