Sort columns of a table by the value corresponding

33 vues (au cours des 30 derniers jours)
Turner
Turner le 19 Fév 2023
Commenté : Ron le 29 Juin 2024
Ive attached a sc of my table, although it continues to 86 columns, I would like to sort the values corresponding to each variable in decending order, and have the variable names be sorted along with the value.
The table dimensions is 1x86 as seen in the screenshot
  3 commentaires
Turner
Turner le 20 Fév 2023
Row 1 sorted in descending order. I'm able to do that if I just take row 1 and make it an array and use sort(), but then the names of each column are no longer associated with the correct numerical value, so I can't label a figure correctly. So basically I'm trying to get the row sorted in decending order while its still a table so each value is aligned with its correct variable name.
An open ended project, but yes hw essentially.
Stephen23
Stephen23 le 20 Fév 2023
Modifié(e) : Stephen23 le 20 Fév 2023
If the table was arranged transposed, then this would be trivial using SORTROWS():
V = [0.141;0;0.0146;0.0045;0.0567];
T = table(V,'RowNames',{'H','He','Li','Be','B'})
T = 5×1 table
V ______ H 0.141 He 0 Li 0.0146 Be 0.0045 B 0.0567
T = sortrows(T,'V')
T = 5×1 table
V ______ He 0 Be 0.0045 Li 0.0146 B 0.0567 H 0.141
Better data design makes code simpler, more robust, and more efficient.

Connectez-vous pour commenter.

Réponse acceptée

Walter Roberson
Walter Roberson le 20 Fév 2023
[~, idx] = sort(table2array(YourTable), 2, 'descend');
out = YourTable(:, idx) ;
Note that this implementation will only work for a single row, as it rearranges the table object. If you needed multiple rows then the variable names would have to be mixed with the numeric values, which is possible with a change of representation.
  2 commentaires
Turner
Turner le 20 Fév 2023
Which representation would be the best to change it to in order to keep the variable names associated with each value? As that is what I'm attempting
Walter Roberson
Walter Roberson le 20 Fév 2023
My proposal is the same as what Voss suggested, just that I tend to use different helper functions, such as
[~,idx] = sort(table2array(T),'descend');
The crucial step is taking the sort order information from sort() and using it to index the table variables, which re-arranges the table to have the variables in that order.
The "different representation" I was referring to would apply to the case where you had multiple rows in the table and wanted to process each row individually: in such a case you would not be able to have two different variable orders in two different rows of the same table() object. In such a situation you could use representations such as
'Li', 0.146, 'H', 0.141, 'He', 0
'H', 0.314, 'Li', 0.11', 'C', 0.04
right inside the table, with odd-numbered variables being element abbreviations and the even-numbered variables being the coefficient that went with it.
Or you could use the data to construct a table such as
'Li: 0.146', 'H: 0.141', 'He: 0'
'H: 0.314', 'Li: 0.11', 'C: 0.04'
with text for all entries. Or you might prefer text but
'0.146: Li', '0.141: H', '0: He'
'0.314: H', '0.11: Li', '0.04: C'
The method that I had suggested, and which Voss showed explicit code for, works fine for a single row; you only need to care about alternate forms if you have multiple rows.

Connectez-vous pour commenter.

Plus de réponses (1)

Voss
Voss le 20 Fév 2023
% I make a table of random data with 10 columns and 1 row, to represent your table
C = num2cell(rand(1,10));
T = table(C{:},'VariableNames',cellstr(('A':'J').'))
T = 1×10 table
A B C D E F G H I J _______ ______ _______ _______ _______ _______ ______ _______ ______ _______ 0.87544 0.0112 0.93254 0.65738 0.71669 0.62776 0.3965 0.90837 0.8422 0.10215
% sort the values, descending
[~,idx] = sort(T{:,:},'descend');
% reorder the table columns
T = T(:,idx)
T = 1×10 table
C H A I E D F G J B _______ _______ _______ ______ _______ _______ _______ ______ _______ ______ 0.93254 0.90837 0.87544 0.8422 0.71669 0.65738 0.62776 0.3965 0.10215 0.0112
  4 commentaires
Walter Roberson
Walter Roberson le 28 Juin 2024
sortrows(Data, 9, 'descending')
Ron
Ron le 29 Juin 2024
Thankyou so much for taking out time and replying to my question. Although I was able to find out that one of the elements was a string instead of numeric and thats why I was not able to sort to but thankyou once again for helping.

Connectez-vous pour commenter.

Catégories

En savoir plus sur Shifting and Sorting Matrices dans Help Center et File Exchange

Tags

Produits


Version

R2022b

Community Treasure Hunt

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

Start Hunting!

Translated by