How to use if inside loop

I'm working on matlab code for counting number of reflection, here is my code

 RY=30;
L_B=40;
L_S=20;
% Single Reflection Left Side
if RY < 2*L_B
    R1L=1     %  1                   
elseif 2*L_B<RY && RY< 2*(L_B+L_S)
    R1L=0     %  3
elseif 2*(L_B+L_S) < RY && RY< 2*(2*L_B+L_S)
    R1L=1     %  5
elseif 2*(2*L_B+L_S) < RY && RY< 2*(2*L_B+2*L_S)
    R1L=0     %  7
elseif 2*(2*L_B+2*L_S) < RY && RY< 2*(3*L_B+2*L_S)
    R1L=1     %  9
elseif 2*(3*L_B+2*L_S) < RY && RY< 2*(3*L_B+3*L_S)
    R1L=0     %  11
elseif 2*(3*L_B+3*L_S) < RY && RY< 2*(4*L_B+3*L_S)
    R1L=1     %  13
else
    R1L=0
end
% Single Reflection Right Side
if RY < 2*L_B
    R1R=1     %  2                   
elseif 2*L_B<RY && RY< 2*(L_B+L_S)
    R1R=0     %  4
elseif 2*(L_B+L_S) < RY && RY< 2*(2*L_B+L_S)
    R1R=1     %  6
elseif 2*(2*L_B+L_S) < RY && RY< 2*(2*L_B+2*L_S)
    R1R=0     %  8
elseif 2*(2*L_B+2*L_S) < RY && RY< 2*(3*L_B+2*L_S)
    R1R=1     %  10
elseif 2*(3*L_B+2*L_S) < RY && RY< 2*(3*L_B+3*L_S)
    R1R=0     %  12
elseif 2*(3*L_B+3*L_S) < RY && RY< 2*(4*L_B+3*L_S)
    R1R=1     %  14
else
    R1R=0
end 
  Total=R1L+R1R

When it is executed, Total=2

However, I want to change variable RY to from 1 to 200 with step=1 so the size of Total is 200x1 How I supposed to do with looping?

Answer 1

[Akira Agata]

I think the following will solve your problem.

 Total = zeros(200,1);
 for kk = 1:200
    RY = kk;
    L_B=40;
    L_S=20;
    % Single Reflection Left Side
    if RY < 2*L_B
        R1L=1;     %  1
    elseif 2*L_B<RY && RY< 2*(L_B+L_S)
        R1L=0;     %  3
    elseif 2*(L_B+L_S) < RY && RY< 2*(2*L_B+L_S)
        R1L=1;     %  5
    elseif 2*(2*L_B+L_S) < RY && RY< 2*(2*L_B+2*L_S)
        R1L=0;     %  7
    elseif 2*(2*L_B+2*L_S) < RY && RY< 2*(3*L_B+2*L_S)
        R1L=1;     %  9
    elseif 2*(3*L_B+2*L_S) < RY && RY< 2*(3*L_B+3*L_S)
        R1L=0;     %  11
    elseif 2*(3*L_B+3*L_S) < RY && RY< 2*(4*L_B+3*L_S)
        R1L=1;     %  13
    else
        R1L=0;
    end
    % Single Reflection Right Side
    if RY < 2*L_B
        R1R=1;     %  2
    elseif 2*L_B<RY && RY< 2*(L_B+L_S)
        R1R=0;     %  4
    elseif 2*(L_B+L_S) < RY && RY< 2*(2*L_B+L_S)
        R1R=1;     %  6
    elseif 2*(2*L_B+L_S) < RY && RY< 2*(2*L_B+2*L_S)
        R1R=0;     %  8
    elseif 2*(2*L_B+2*L_S) < RY && RY< 2*(3*L_B+2*L_S)
        R1R=1;     %  10
    elseif 2*(3*L_B+2*L_S) < RY && RY< 2*(3*L_B+3*L_S)
        R1R=0;     %  12
    elseif 2*(3*L_B+3*L_S) < RY && RY< 2*(4*L_B+3*L_S)
        R1R=1;     %  14
    else
        R1R=0;
    end
    Total(kk)=R1L+R1R
 end

Answer 2

[Andrei Bobrov]

RY = 1:200;
L_B = 40;
L_S = 20;
LL = [L_B;L_S];

r = repelem((1:3)',2);
lgt = 2*toeplitz([0;r;4],[0 0])*[L_B;L_S];
lgt(1) = -inf;
lgt = [lgt;inf];

Total = 2*rem(discretize(RY,lgt),2);