how to delete same data

i have data

 12  0  26  94  1011
12  30  26  100  1011
1  0  26  94  1011
1  30  26  94  1011
*2  0  26  95  1011
2  0  26  94  1011*
2  30  26  100  1010
3  0  26  100  1010
3  30  26  100  1010
4  0  26  94  1009
4  30  25  100  1009
*5  0  25  99  1009
5  0  25  100  1009*
5  30  26  100  1009

i want to delete same data , so the data became that.

12  0  26  94  1011
12  30  26  100  1011
1  0  26  94  1011
1  30  26  94  1011
2  0  26  95  1011
2  30  26  100  1010
3  0  26  100  1010
3  30  26  100  1010
4  0  26  94  1009
4  30  25  100  1009
5  0  25  99  1009
5  30  26  100  1009

i have tired , using unique.. thanks

[Innosens]

the reference is in column 2 , pattern formed is 0, 30. but in column 2 row 5 and 6 is same, row 13 and row 14 is same

2  0  26  95  1011
2  0  26  94  1011
5  0  25  99  1009
5  0  25  100  1009

[Walter Roberson]

You only have two distinct values in column 2, so deleting all the duplicates based on those values alone would give you just two rows of results.

Are you looking for unique values based on the combination of column 1 and column 2? If so, then when you find a duplicate, should the first of them be deleted, or the one that has the maximum in one of the other columns, or some other criteria ?

[Innosens]

only column 2, because pattern data like that. this only sample data i want to make easy program because my data is large

12  0  26  94  1011
12  30  26  100  1011
1  0  26  94  1011
1  30  26  94  1011
2  0  26  95  1011
2  30  26  100  1010
3  0  26  100  1010
3  30  26  100  1010
4  0  26  94  1009
4  30  25  100  1009
5  0  25  99  1009
5  30  26  100  1009

any idea?

[Jonathan Epperl]

I don't get it either. You had

5  0  25  99  1009
5  0  25  100  1009

and you deleted the 2nd row, even though the data in column 4 are 99 and 100, respectively. So why is that? Please just state clearly according to which criterion you want to delete rows, or we cannot help you.

[Walter Roberson]

Is the rule that if you have two of the same column 2 value in a row, that you should delete the first of them, no matter what the values are in the other columns?

[Innosens]

walter Roberson one row is removed example

5  0  25  99  1009
5  0  25  100  1009
became
5  0  25  100  1009

Answer 1

[Andrei Bobrov]

a = [ 12  0  26  94  1011
12  30  26  100  1011
1  0  26  94  1011
1  30  26  94  1011
2  0  26  95  1011
2  0  26  94  1011
2  30  26  100  1010
3  0  26  100  1010
3  30  26  100  1010
4  0  26  94  1009
4  30  25  100  1009
5  0  25  99  1009
5  0  25  100  1009
5  30  26  100  1009];

out = a([true;diff(a(:,2)) ~= 0],:);

Answer 2

[Walter Roberson]

There are no duplicate rows in your data; each one has something unique about it. How should it be determined which one to delete? If certain columns are to be ignored in the matching, then should the first of them be deleted, or the one with the maximum in the column not used for matching, or ... ?

[Innosens]

only column 2, because pattern data like that. this only sample data i want to make easy program because my data is large

12  0  26  94  1011
12  30  26  100  1011
1  0  26  94  1011
1  30  26  94  1011
2  0  26  95  1011
2  30  26  100  1010
3  0  26  100  1010
3  30  26  100  1010
4  0  26  94  1009
4  30  25  100  1009
5  0  25  99  1009
5  30  26  100  1009
any idea?