For loop in matlab

Using for or while loops, and without using code in the form "for i=1:2:n or v(1,:)" so statements of the form "for i=1:n and v(1,n)" are okay,I need to write a function that takes a matrix input and a scalar input and returns a new matrix of elements every scalar apart.

For example a=function(magic(4),2) would return

a=[16 3; 9 6]

Anyone have an idea?

Answer 1

[Image Analyst]

Hint:

newMatrix = m(startingIndexR:StepIndexR:endingIndexR, startingIndexC:StepIndexC:endingIndexC)

You can extract a matrix by giving a starting and ending index number and a step or increment value. You can do both rows (first index) and columns (second index) all in the same line of code. Define a function

function output = YourFunctionName(input1, input2)
% Your code goes here....

then do some code to assign "output" and call it from a main program like your homework problem stated.

[eli]

Thanks for the reply I'm not allowed to index a matrix using double colon notation like in your hint "startingIndexR:StepIndexR:endingIndexR" I was able to complete the task using this notation

%retrieves every pixel factor apart from each row b=image(:,1:factor:end);

%retrieves every pixel factor apart from each column c=b(1:factor:end,:);

but now I have to use explicit for or while loops to rewrite this code., and I am really struggling with this.

[Image Analyst]

What a ridiculous requirement. Here's the workaround for that nonsense:

for k = 1 : 20
  if rem(k,2) == 0
    continue;
  end
  k % Print k to command line
end

Now, in the loop assign your matrix. You might want to use a counter or else divide k by 2.