index for max value and vector indexing vectorize

Hello all, I have two questions. I am dealing with both because I want to avoid using loop in order to save computation time. So I am looking for solutions which do not use loop.

1. I have two huge three dimensional matrices which I want to compare between. Here I am giving a short example.

x(:,:,1) =

     3     7 

     6     8

x(:,:,2) =

     6     7 

     4     8

x(:,:,3) =

     9     7 

     5     1

and

y(:,:,1) =

     5     6   

     7     2

y(:,:,2) =

     4     9     

     7

y(:,:,2) =

     1     5   

     3     6

First I want to find max values in x(:,:,1) which would be 8 and compare it with the max value in y(:,:,1) which would be 7; next, I find max value in x(:,:,2) which would be 8 and compare it with max value in y(:,:,2) which would be 9; and finally I go on finding max value in x(:,:,3) which would be 9 and compare it with the max value in which is 6. My goal is to find the index of the maximum value in each case in a vector, like

a =[2,2;

1,2;

1,1];

the first row in a 2,2 indicates the index (row and column) of 8 (the ma value between x(:,:,1) and y(:,:,1). The second row in a 1,2 indicates the index of 9 from my comparison of x(:,:,2) and y(:,:,2) and finally the last row 1,1 indicates the index of 9 from my comparison of x(:,:,3) and y(:,:,3). My question is how do I construct vector a without loop.

2. I have the following variables

x=[15 25; 13 22; 15 22];

s=x(:,1);

as=x(:,2);

k=zeros(3,44);

k(:,as-22+s-12+1:44)=(as-22:1:65-22-(s-12));

My objective is to fill inside k. I am not able to do so. If correctly done, I should get the following.

k =

Columns 1 through 21

     0     0     0     0     0     0     3     4     5     6     7     8     9    10    11    12    13    14    15    16    17
     0     0     1     2     3     4     5     6     7     8     9    10    11    12    13    14    15    16    17    18    19
     0     0     0     0     1     2     3     4     5     6     7     8     9    10    11    12    13    14    15    16    17

Columns 22 through 42

    18    19    20    21    22    23    24    25    26    27    28    29    30    31    32    33    34    35    36    37    38
    20    21    22    23    24    25    26    27    28    29    30    31    32    33    34    35    36    37    38    39    40
    18    19    20    21    22    23    24    25    26    27    28    29    30    31    32    33    34    35    36    37    38

Columns 43 through 44

    39    40
    41    42
    39    40

I appreciate any help.

Thanks, Melaku