MATLAB: Rewrite the loop – whats wrong with that loop

MATLABsimulink

Hi, I did rewrite my code – matlab functionas you can see below:
            _if(dir1==1) 
                 if(I1>0)
                     if(ADDR1==1)
                        [~, I] = sort(V1,'ascend'); 
                        SMh1(I(1:ADDR1)) = 1;
                     elseif(ADDR1>1 && ADDR1<20)
                        [~, I] = sort(V1,'ascend'); 
                        SMh1(I(ADDR1:ADDR1)) = 1;
                     elseif(ADDR1==20)
                        SMh1(:) = 1; 
                     end
                 else
                     if(ADDR1==1)
                        [~, I] = sort(V1,'descend'); 
                        SMh1(I(1:ADDR1)) = 1;
                     elseif(ADDR1>1 && ADDR1<20)
                        [~, I] = sort(V1,'descend'); 
                        SMh1(I(ADDR1:ADDR1)) = 1;
                     elseif(ADDR1==20)
                        SMh1(:) = 1; 
                     end
                 end
             else
                 if(I1>0)
                     if(ADDR1==19)
                        [~, I] = sort(V1,'ascend'); 
                        SMh1(I(1:N_SM-ADDR1)) = 0;
                     elseif(ADDR1<19 && ADDR1>1)
                        [~, I] = sort(V1,'ascend'); 
                        SMh1(I(N_SM-ADDR1:N_SM-ADDR1)) = 0;
                     elseif(ADDR1==0)
                        SMh1(:) = 0; 
                     end
                 else
                     if(ADDR1==19)
                        [~, I] = sort(V1,'descend'); 
                        SMh1(I(1:N_SM-ADDR1)) = 0;
                     elseif(ADDR1<19 && ADDR1>1)
                        [~, I] = sort(V1,'descend'); 
                        SMh1(I(N_SM-ADDR1:N_SM-ADDR1)) = 0;
                     elseif(ADDR1==0)
                        SMh1(:) = 0; 
                     end
                 end
             end_
        The input to that function are: ADDR1,dir1,I1,V1
        The output is SMh1.
        V1 is kind a vector of 20 elements, like V1=[23 42 7 12 93...61 90].
        V1 is input and it changing as far as ADDR1 increasing/decreasing.
        SMhl is the output of that function.
        SMh1 is a vector of 20 elements and should filled with 0 or 1 depending on the code above.
        for example:
        if ADDR1 = 0 
           SMhl = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0] -> not depend on values of V1. 
        when ADDR1 = 1... there is dependent on V1,dir1 and I1:
             for dir1=1 and I1>0 the function should search the first min values fo V1, and indicate the SMh1 to 1.
             The index of that bit should be the index of min V1:
        for example:
                   *ADDR1 = 1*
                   dir1=1 and  I1>0 
                   V1 = [84 82 21 25 26 54 57 74 43 61 98 87 33 66 49 71 *19* 80 30 51]
                   SMhl [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 *1* 0 0 0]
                   *ADDR1 = 2*
                   dir1=1 and  I1>0 
                   V1 = [14 22 33 55 76 54 37 44 43 51 28 37 33 86 99 61 29 43 *10* 31]
                   SMhl = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 *1* 0 *1* 0]
                   *ADDR1 = 3*
                   dir1=1 and  I1>0 
                   V1 = [ *34* 44 55 66 77 88 84 62 87 47 90 72 68 51 39 79 93 82 101 131]
                   SMhl = [ *1* 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 *1* 0 *1* 0]
..................................
..................................
..................................
                   *ADDR1 = 20*
                   dir1=1 and  I1>0 
                   V1 = [34 44 55 66 77 88 84 62 87 47 90 72 68 51 39 79 93 82 101 131]
                   SMhl = [ *1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1*]
the algorytm should be like that: —> depending on the location of min V1(the index). when dir1=1, search min values and set SMhl bit to 1 when dir1=0, search min values and set SMhl bit to 0 when I1<0 –> the function do the same but search for mav V1.
Somthing does not works proper in that function. I am stuck and really need for help.
Can soeone help me to solve it ?
Thanks, Henry

Best Answer

I think you can rewrite your code as follows:
if dir1 == 1
  addr = ADDR1;  val = 1;
else
  addr = N_SM - ADDR1; val = 0;
end
if I1 > 0
  [~, idx] = sort(V1, 'ascend'); 
else
   [~, idx] = sort(V1, 'descend');
end
idx = idx(find(SMh1(idx) == 0, 1, 'first'));
 % use addr, val, and idx:
 if ADDR1 >= 1 && ADDR1 < 20
   SMh1(idx) = val;
 elseif ADDR1 == 20
  SMh1(:) = val; 
 end 
 % output
 SMh1
Then it is much easier to debug under which condition the code does not do what you intend to do.
Related Question