How to extract all rows that only one columns has a value greater than?

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Hi all,
I have a quick question. I have A as a 5000 x 30 table. I want to to see which cells have a value greater than 50 and extract the entire corresponding row. How should I do that?
Thanks in advance.

Accepted Answer

Star Strider
Star Strider on 21 May 2021
Edited: Star Strider on 21 May 2021
One approach —
T1 = array2table(randi(60,15, 7))
T1 = 15×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____ ____ ____ ____ ____ ____ ____ 12 9 56 23 12 3 8 37 49 4 59 14 16 41 46 48 13 6 11 53 3 43 33 16 44 6 7 48 57 4 40 40 51 54 52 5 3 46 2 4 57 30 22 43 32 1 26 52 32 56 14 38 55 46 4 9 43 2 20 53 6 32 21 35 4 27 9 22 6 7 28 9 37 35 24 49 37 47 30 14 53 49 23 9 29 16 57 28 27 15 10 15 32 56 49 55 39 38 47 17 7 29 18 8 1
idx = any(T1{:,:}>50,2); % Logical Row Index
T1_extracted = T1(idx,:)
T1_extracted = 11×7 table
Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____ ____ ____ ____ ____ ____ ____ 12 9 56 23 12 3 8 37 49 4 59 14 16 41 46 48 13 6 11 53 3 57 4 40 40 51 54 52 5 3 46 2 4 57 30 22 43 32 1 26 52 32 56 14 38 55 46 4 9 43 2 20 53 6 32 21 47 30 14 53 49 23 9 29 16 57 28 27 15 10 15 32 56 49 55 39 38
EDIT — (21 May 2021 at 15:52)
Added timetable operations and result —
T1T = [table(datetime('now')+hours(0:size(T1,1)-1)', 'VariableNames',{'Time'}) T1]
T1T = 15×8 table
Time Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____________________ ____ ____ ____ ____ ____ ____ ____ 21-May-2021 15:50:17 12 9 56 23 12 3 8 21-May-2021 16:50:17 37 49 4 59 14 16 41 21-May-2021 17:50:17 46 48 13 6 11 53 3 21-May-2021 18:50:17 43 33 16 44 6 7 48 21-May-2021 19:50:17 57 4 40 40 51 54 52 21-May-2021 20:50:17 5 3 46 2 4 57 30 21-May-2021 21:50:17 22 43 32 1 26 52 32 21-May-2021 22:50:17 56 14 38 55 46 4 9 21-May-2021 23:50:17 43 2 20 53 6 32 21 22-May-2021 00:50:17 35 4 27 9 22 6 7 22-May-2021 01:50:17 28 9 37 35 24 49 37 22-May-2021 02:50:17 47 30 14 53 49 23 9 22-May-2021 03:50:17 29 16 57 28 27 15 10 22-May-2021 04:50:17 15 32 56 49 55 39 38 22-May-2021 05:50:17 47 17 7 29 18 8 1
TT1 = table2timetable(T1T);
idx = any(TT1{:,:}>50,2); % Logical Row Index
TT1_extracted = TT1(idx,:)
TT1_extracted = 11×7 timetable
Time Var1 Var2 Var3 Var4 Var5 Var6 Var7 ____________________ ____ ____ ____ ____ ____ ____ ____ 21-May-2021 15:50:17 12 9 56 23 12 3 8 21-May-2021 16:50:17 37 49 4 59 14 16 41 21-May-2021 17:50:17 46 48 13 6 11 53 3 21-May-2021 19:50:17 57 4 40 40 51 54 52 21-May-2021 20:50:17 5 3 46 2 4 57 30 21-May-2021 21:50:17 22 43 32 1 26 52 32 21-May-2021 22:50:17 56 14 38 55 46 4 9 21-May-2021 23:50:17 43 2 20 53 6 32 21 22-May-2021 02:50:17 47 30 14 53 49 23 9 22-May-2021 03:50:17 29 16 57 28 27 15 10 22-May-2021 04:50:17 15 32 56 49 55 39 38
.

More Answers (2)

Image Analyst
Image Analyst on 21 May 2021
Try this:
% Convert your table tA to a double matrix called dA.
dA = table2array(tA);
% Find out which rows have any values more than 50.
rowsToTextract = any(dA > 50, 2)
% Extract only those rows. You can get a new double variable
% and/or a new table variable. I show both ways.
A50 = dA(rowsToTextract, :) % As a double matrix variable
t50 = tA(rowsToTextract, :) % As a table variable

David Hill
David Hill on 21 May 2021
a=table2array(yourTable);
[idx,~]=find(a>50);
a=a(unique(idx),:);%this should give you what you are looking for
  1 Comment
Wolfgang McCormack
Wolfgang McCormack on 21 May 2021
@David Hill thank you David. Any solution for timetables? because turning the time table to an array will cause a lot of mess for me. It's a sorted table based on time (with a lot of gaps) and turning it to an array won't allow me to use the histogram for monthyl values.

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