How to solve loop equation with given data

Dear all,

I want to solve the equation below.

first column of excel sheet is 'a' and 2nd column is 'b' coresponding to 'a'. For each a, there is m in the interval 0 to 3 with increment of 0.01 (m=0:0.01:3). How to solve ?

[Adam Danz]

"I want to solve the equation below."

What have you tried so far?

[Manish Kumar]

I have tried

m = 0:0.01:3
for i=1:421 
  eff(i,:) = ((0.65.*(a(i)-m-0.3).*b(i)))./10 
end

[KSSV]

What is your problem? You got it right? Do intialze the variable in loop: beofre loop begins

eff = zeros(421,301) ; 

[Adam Danz]

Yeah, this looks right. Just initialize 'eff' as KSSV recommended. Any other questions?

[Manish Kumar]

I have tried

m = 0:0.01:1

eff = zeros(421,301)

for i=1:421

eff(i,:) = ((0.65.*(a(i)-m-0.3).*b(i)))./10 ;

end

xlswrite ('1.xlsx',[a(:),m(:),eff(:)]);

error is coming:

Unable to perform assignment because the indices on the left side are not

compatible with the size of the right side.

[Adam Danz]

The reason it stopped working is because you changed the size of 'm' but didn't change the size of 'eff'. I added a solution below that corrects this and allows you to use any size of 'm' without needing to change the size of 'eff'.

Answer 1

[Adam Danz]

(continuing from the comments under the question to that the question is answered).

The more responsible way to initialize the loop variable is by using variables rather than hard-coding the variable size.

a = 1:1000;
b = 1:1000;
m = 0:0.01:3
n = 421; %number of loops
eff = zeros(n,length(m))  %here we use 'n' and the size of 'm' to define 'eff'
for i=1:n
  eff(i,:) = ((0.65.*(a(i)-m-0.3).*b(i)))./10 ;
end