Defining multiple variables in a single loop

Good afternoon,

I am trying to define three variables in a loop a,b and c in the following way:

for a=2:49

for b= 52:99

for c=1:48

derives(a)= x(b)/m;

derives(b) = k*x(c)- 2*k*x(c+1)+ k*x(c+2);

end

end

end

But this method does not give me the results I want, In fact my supervisor told me that I am not using a loop at all!

I tried putting the code between each for loop, but then the other variables are undefined

Could anyone please suggest an alternative method in which I can define all three variables in a for loop?

Thanks

Answer 1

[Steven Lord]

You are, of course, using a loop. I suspect what your supervisor told you (or intended to tell you) is that you don't need to use loops here. You can vectorize the calculations by operating on pieces of the x array that are larger than single elements.

x = 1:5;
whereToStore = 3 + (1:numel(x)); % Store in elements 4 (3+1) to 8 (3+5)
y(whereToStore) = x.^2

y = 1×8

0 0 0 1 4 9 16 25

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