How to call a specific element of a table

4 Ansichten (letzte 30 Tage)
Zeynab Mousavikhamene
Zeynab Mousavikhamene am 29 Aug. 2019
Bearbeitet: Andrei Bobrov am 30 Aug. 2019
I want to
find the "radius" in which "time" is 2 and p"erhexagon" is 2.1667. There might be more than one radius that matches this criteria.
Any suggestion?
  2 Kommentare
KALYAN ACHARJYA
KALYAN ACHARJYA am 29 Aug. 2019
Bearbeitet: KALYAN ACHARJYA am 29 Aug. 2019
Have you check here?
Still unable to resolve it, please attach the table.
madhan ravi
madhan ravi am 29 Aug. 2019
Learn to attach data as .mat file as shown by Andrei below, attaching a screenshot is useless!

Melden Sie sich an, um zu kommentieren.

Akzeptierte Antwort

Adam Danz
Adam Danz am 29 Aug. 2019
Bearbeitet: Adam Danz am 29 Aug. 2019
Assuming your table is named "T",
% find the rows where time equals 2 and perhexagon equals exactly 2.1667
rowidx = T.time == 2 & T.perhexagon == 2.1667;
% use the row index to get the chosen radii
chosenRads = T.radius(rowidx);
Note that if you have trouble matching the floating point decimals, you may have to build in a tolerance instead of requiring an exact match. Example below.
% Define tolerance
tol = 0.001; %accepted if perhexagon value is +/-tol from target
% find the rows where time equals 2 and perhexagon equals exactly 2.1667
rowidx = T.time == 2 & abs(T.perhexagon - 2.1667)<tol;
  2 Kommentare
Zeynab Mousavikhamene
Zeynab Mousavikhamene am 29 Aug. 2019
Bearbeitet: Zeynab Mousavikhamene am 29 Aug. 2019
Thanks.
I tried:
% find the rows where time equals 2 and perhexagon equals exactly 2.1667
rowidx = Acc_cellcount.time == 2 & Acc_cellcount.perhexagon == 2.1667;
% use the row index to get the chosen radii
chosenRads = Acc_cellcount.radius(rowidx);
and it came out:
chosenRads =
0×1 empty double column vector
Adam Danz
Adam Danz am 29 Aug. 2019
This is where my "note" comes in at the end of my answer. Your "perhexagon" values aren't really 2.1667. Those are just the first 4 decimal places. So you need to build in a tolerance. For example, accept any rows where perhexagon is within 0.0001 within the target value. I'll update my answer.

Melden Sie sich an, um zu kommentieren.

Weitere Antworten (1)

Andrei Bobrov
Andrei Bobrov am 29 Aug. 2019
Bearbeitet: Andrei Bobrov am 29 Aug. 2019
load data.mat
lo = ismembertol(T{:,{'time','perhexagon'}},[2,2.1667],'ByRows',true,...
'DataScale',[1 .00001]);
out_radius = T.radius(lo);
  2 Kommentare
Zeynab Mousavikhamene
Zeynab Mousavikhamene am 29 Aug. 2019
Bearbeitet: Zeynab Mousavikhamene am 29 Aug. 2019
Got this error:
Error using load
Unable to read file 'data.mat'. No such file or directory.
I run for the second time without "Error using load" and I got :
"out_radius =
0×1 empty double column vector"
Tried multiple 'DataScales': [1 .001] or [1 .1] or [1]
all gave empty out_radius.
Andrei Bobrov
Andrei Bobrov am 30 Aug. 2019
Bearbeitet: Andrei Bobrov am 30 Aug. 2019
You do not know how to download, sorry.
Exsample my laptop with Ubuntu (I from Russia :) ):
>> load '/home/andrei/Загрузки/data.mat'
>> lo = ismembertol(T{:,{'time','perhexagon'}},...
[2,2.1667],'ByRows',true,'DataScale',[1 .00001]);
out_radius = T.radius(lo)
out_radius =
1
2
>>

Melden Sie sich an, um zu kommentieren.

Kategorien

Mehr zu Tables finden Sie in Help Center und File Exchange

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by