creating a new vector relative to the matrix

I have an example matrix:

1 19:20:43 DC 7,102 V AUTO

2 19:20:44 DC 7,103 V AUTO

3 19:20:44 DC 7,105 V AUTO

4 19:20:45 DC 7,105 V AUTO

5 19:20:46 DC 6,105 V AUTO

6 19:20:47 DC 1,105 V AUTO

7 19:20:48 DC 0 V AUTO

8 19:20:48 DC 0 V AUTO

9 19:20:49 DC 1 V AUTO

10 19:20:50 DC 7,105 V AUTO

I’ d like to create a new vector, which will assign to time from a first row of matrix (19:20:43) value 1, to time from second row (19:20:44) – value 2 e.c.t.. But if the time value repeats, assign the same value for both time values. For matrix above, new vector should be t=[1;2;2;3;4;5;6;6;7;8].

I should probably use loop for, and function if, but really don’t know how to do it.

I hope you understood my problem :)

Answer 1

[Nobel Mondal]

% A = your 10x6 original matrix;

uRows = unique(A, 'rows');
result = zeros(6,1);

for i=1:size(uRows, 1)
    cols = find(ismember(A, uRows(i,:), 'rows'));
    result(cols) = i;
end

Answer 2

[Muhammad Usman Saleem]

clear some questions for me. what is the size of the following matrix? how many rows and column it has?

1 19:20:43 DC 7,102 V AUTO

2 19:20:44 DC 7,103 V AUTO

3 19:20:44 DC 7,105 V AUTO

4 19:20:45 DC 7,105 V AUTO

5 19:20:46 DC 6,105 V AUTO

6 19:20:47 DC 1,105 V AUTO

7 19:20:48 DC 0 V AUTO

8 19:20:48 DC 0 V AUTO

9 19:20:49 DC 1 V AUTO

10 19:20:50 DC 7,105 V AUTO

tell me are these 10 different matrixs or only single one? As matrix has same data type.i am getting confuse you are using numeric and string in matrix.This should be structure case..

Answer 3

[Przemyslaw Kaluski]

It was my .xls data file before importing it to matlab, sorry for that.

This is my one matrix 10x6

0 0 0 19 20 43

0 0 0 19 20 44

0 0 0 19 20 44

0 0 0 19 20 45

0 0 0 19 20 46

0 0 0 19 20 47

0 0 0 19 20 48

0 0 0 19 20 48

0 0 0 19 20 49

0 0 0 19 20 50

4th column is hour, 5th is minute, 6th is second of measure. I'd like to create a new vector t, which will assign to time value from a first row of matrix (0 0 0 19 20 43) value 1, to time value from second row (0 0 0 19 20 44) – value 2 e.c.t.. But if the time value repeats, assign the same value for both time values. For matrix above, new vector should be t=[1;2;2;3;4;5;6;6;7;8].

Answer 4

[Przemyslaw Kaluski]

It works, thank you.

I made another script by myself, but it doesn't run, don't know why. Could you tell me what is wrong with it? Sorry for messing, I'm new at Matlab and I'd like to know where I make mistakes :)

t=[];
t(1,1)=1;
for i=1:length(z);
    if z(i+1,6)=z(i,6)
        t(1+i,1)=i;
    else
        t(1+i,1)=i+1;
    end

[Nobel Mondal]

This code would strictly hold up for the values that you have shown in the question. But, say what about when the minutes (column 5) change as well.

Anyway, assuming z is your original 10x6 matrix, the condition checking line is incorrect.

if z(i+1,6)==z(i,6); % Use '==' not the assignment operation '='