how to edit this matrix

I have a matrix B that has three columns. A week number is in the first column, a day number is in the second column, and data is in the third column.

B=
1       6       9
3  15  11
4  23  11
5  30  11
6  37  12
6  38  11
6  39  10
9  58  12
10  65  13

What I want to do is turn this into a matrix with 10 rows, one for each week. Whenever there is a week with no data, like week 2 and week 7, I want to add a row with the proper week number, but zeros for the day number and the data. Also, whenever there is a week with more than 1 data entry, like week 6, I want to convert that to one row with 6 as the week number, any value for the day number, and the mean of the data values as the one data value. In other words, I want to convert matrix B into:

C= 
1       6       9
2       0       0
3  15  11
4  23  11
5  30  11
6  38  11
7       0       0
8       0       0
9  58  12
10  65  13

How can I go about doing this?

[Walter Roberson]

I notice you have edited the question, but as I read, I do not notice the difference between the current version and the original ?

Answer 1

[Walter Roberson]

widx = B(:,1);
dayvec = accumarray(widx, B(:,2), [], @min);
valvec = accumarray(widx, B(:,3), [], @mean);
C = [(1:max(widx)).', dayvec(:), valvec(:)];

[Michael]

Thank you! This works well, my only question would how could I make it so that if the 10th week was missing, it would fill in a tenth week without stopping at 9?

[Walter Roberson]

Replace the [] with [10 1]

[Michael]

It was telling me that the dimensions of the matrices being concatenated are not consistent, so I added another line, and ran it like this, and it worked:

MATLAB CODE
widx = B(:,1)
weekvec = accumarray(widx, B(:,1), [10, 1], @min)    added this line
dayvec = accumarray(widx, B(:,2), [10 1], @min)
valvec = accumarray(widx, B(:,3), [10 1], @mean)
C = [(1:length(weekvec))', dayvec(:), valvec(:)]   used weekvec here

is there a cleaner way of doing this?

[Walter Roberson]

Setting weekvec like that is not needed. Leave that line out and use

C = [(1:length(dayvec)).', dayvec(:), valvec(:)];

[Michael]

Ahh yes, that makes way more sense, thanks