# How to extract row intervals from a table to create a new one.

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Philippe Corner on 31 Jan 2018
Commented: Peter Perkins on 7 Feb 2018
if I have a table
T:
v1 v2 v3 v4
a 1 1 5
b 3 3 7
c 2 5 7
d 5 5 2
e 5 7 7
How could i obtain all the columns from b and d rows as T2 table?
T2:
v1 v2 v3 v4
b 3 3 7
c 2 5 7
d 5 5 2

Walter Roberson on 31 Jan 2018
Edited: Walter Roberson on 31 Jan 2018
T2 = T1(2:4,:);
Philippe Corner on 1 Feb 2018
Thanks Mr. Walter, it is showing a mistake due to the == when I adapted it to my code.. do you have an idea why could it be?
Walter Roberson on 1 Feb 2018
Edited: Walter Roberson on 1 Feb 2018
The == could have difficulty depending on the data type involved. Perhaps you need
first_row = find(strcmp(T1.v1, 'b'), 1, 'first');
last_row = find( strcmp(T1.v1, 'd'), 1, 'first');

Peter Perkins on 1 Feb 2018
Walter interpreted "all the columns from b and d rows" as "FROM b TO d". I'm going to interpret it as "b AND d".
If the first variable in T has unique values, turn it into the row names, and just subscript:
T.Properties.RowNames = T.Var1;
T.Var1 = [];
t({'b' 'd'},:)
If they're not unique, use ismember to create a logical vector to use as a row subscript.
Walter Roberson on 1 Feb 2018
No, notice they wanted three lines of results, which can only be explained by wanting a range.
Peter Perkins on 7 Feb 2018
right you are.