creating a new column in a matrix using 'if condition"

On the following matrix:

I am using the following code which is not giving the right response.

if Reg1(:,3)==0
    Reg1(:,10)=0;
else
    Reg1(:,10)=a1-b1*Reg1(:,3)+Reg1(:,6);
end

Cannot figure out the issue.

The output is

[Catalytic]

We have no way of knowing what you consider to be the "right response"....

Answer 1

[Stephen23]

IF will not help you in this situation.

You need to use indexing, e.g.:

Reg1(:,10) = a1-b1*Reg1(:,3) + Reg1(:,6);
idx = Reg1(:,3)==0;
Reg1(idx,10) = 0

[Milan Kumar]

Thank you. Works for me.

Answer 2

[Matt J]

if all( Reg1(:,3)==0 )
    Reg1(:,10)=0;
else
    Reg1(:,10)=a1-b1*Reg1(:,3)+Reg1(:,6);
end

[Milan Kumar]

Not working.