can any one explain this line of the code.

Data=[-1 -0.5  1 2; -4 -3 2 3];
m=2.5;  % slope is kept constant
c=-10:0.1:10;  % different values for intercept c to plot the cost
Cost=zeros(1,length(c));
for i=1:length(c)
    Cost(i)=(1/4)*sum( (Data(2,:)'-(m*Data(1,:)'+c(i))).^2);
end

The line in side for loop.

Data(2,:)=[ -4,-3 2 3]'

m*Data(1,:)=2.5*[-1 -0.5 1 2]'

c(1)=-10

How can we add m*Data(1,:)+(-10)

Answer 1

[Bob Thompson]

Per matrix math rules, when you add a single value to a matrix, that operation is applied to all values of the matrix individually.

>> Data(1,:)
    
    -1  -0.5  1  2

>> m*Data(1,:)

    -2.5  -1.25  2.5  5
    
>> m*Data(1,:)

    -12.5  -11.25  -7.5  -5

[sadiqa ilyas]

Thank u