How can I remove for loop in the following code that change the entries of a given vector?

Hello, I am trying to vectorize the following simple code

if true
A=[-1;3;0;-4];
B=zeros(size(A));
for i=1:4
  if A(i)<0
      B(i)=-(A(i));
  elseif A(i)==0
      B(i)=1;
  else
      B(i)=A(i);
  end
  B=B(:);
end  

end
Please, how do I write the above code in such a way that there is no for loop, and still it works?

[Matt J]

Please indent your code, but not your text. It makes your post hard to read, otherwise.

[Hassan]

Ok

Answer 1

[Star Strider]

Try this:

A=[-1;3;-2;-4];
B = A;
B(A<0) = -A(A<0)

[Hassan]

Yes. This a nice simple answer. Thanks.

[Star Strider]

As always, my pleasure.

[Hassan]

But what do you think if the vector A contains zero entry and I need to replace it with any number greater zero?

[Star Strider]

This works:

A=[-1;3;0;-2;-4;0];
B = A;
B(A<0) = -A(A<0)                                            % Change Sign Of ‘A<0’
B(A==0) = randi(9, size(A(A==0),1), size(A(A==0),2))        % Replace Values Of ‘A==0’ With Random Single Integers

I changed ‘A’ to include 2 zero values to demonstrate the code.

[Hassan]

ok

[Star Strider]

Note that it is necessary to determine the number of zeros, so the vector of non-zero values that replaces them is the same size. I used random single-digit positive integers, although any vector with the same number of non-zero values as there are zero values in the vector will work.

Answer 2

[Matt J]

B=abs(A);
B(~A)=1; %or any other value