how to simplify a series of command

hi, I did not study MATLAB systematically so this might be a basic question. is there a common method to simplifying series of commands like the first 34 lines of this file? Thank you.

Answer 1

[Dyuman Joshi]

This is the downside of dynamically naming variables.

Define an array instead of defining variables individually and use a loop -

%Defining an array where one can easily access values via simple indexing 
p=[0,0,2; 2,0,2; 2,0,-1; -2,0,-1; -2,0,0; -1,0,1];

Q=[-1,0,0; 0,0,1; 2,0,0];

s1 = size(Q,1);
s2 = size(p,1);
%pre-allocation
out = zeros(s2,s1);

for m=1:s1
    out(:,m)=1./vecnorm(Q(m,:)-p,2,2);
end
%Here (i,j) element of out corresponds to the value PQipj
out

out = 6×3

0.4472 1.0000 0.3536 0.2774 0.4472 0.5000 0.3162 0.3536 1.0000 0.7071 0.3536 0.2425 1.0000 0.4472 0.2500 1.0000 1.0000 0.3162

Edit - If you have the Stats and ML Toolbox, you can achieve the result in one line of code -

OUT = 1./pdist2(p,Q)

OUT = 6×3

0.4472 1.0000 0.3536 0.2774 0.4472 0.5000 0.3162 0.3536 1.0000 0.7071 0.3536 0.2425 1.0000 0.4472 0.2500 1.0000 1.0000 0.3162

[Dyuman Joshi]

Read more here - Why Variables should not be Named Dynamically