remove rows with duplicates

Consider a following spreadsheet

Column 1 2 3

10 10 10

11 10 9

11 10 10

In this setting I want to delete Row 2 and Row 3 because they have duplicates in Column 1.

More generally, the problem is "I would like to delete any row that has a duplicate in Column 1." Please advise how to proceed

Answer 1

[Walter Roberson]

need_to_delete = [false; any(ismember(YourArray(2:end,:), YourArray(1,:)),2)];
YourArray(need_to_delete, :) = [];