Indexed Assignment on the Right Side

2 visualizzazioni (ultimi 30 giorni)
I am calling function f(x) that returns a matrix of 100 columns.
All what I need is just the 10th column. So I need one vector from the whole returned matrix.
I need to get rid of 99 columns and retain only the 10th column.
In Julia, this can be done by:
columnTen = f(x)[:,10]
I am dying to do the same thing in MATLAB.
Not sure why this simple operation seems impossible.

Risposta accettata

Walter Roberson
Walter Roberson il 17 Nov 2020
columnTen = struct('fx', rand(7,20)).fx(:,10) %needs R2019b or later IIRC
columnTen = 7×1
0.9090 0.8635 0.0364 0.2788 0.2503 0.1882 0.7757
columnTen = subsref(rand(7,20), substruct('()', {':', 10}))
columnTen = 7×1
0.3391 0.0112 0.5269 0.0961 0.5855 0.0371 0.4590
But if you are permitted an initialization beforehand:
Col = @(M,n) M(:,n); %once
ColumnTen = Col(rand(7,20), 10)
  1 Commento
Sinan Islam
Sinan Islam il 18 Nov 2020
Verbose but working. I hope MATLAB make it as simple as other languages. Thank you!

Accedi per commentare.

Più risposte (1)

Andrei Bobrov
Andrei Bobrov il 17 Nov 2020
Y = f(x);
columnTen = Y(:,10);
  1 Commento
Sinan Islam
Sinan Islam il 17 Nov 2020
That is two steps. I need to make the assignment on the fly, in just one line (one operation). I am working with characters. I dont have the option to work on multiple lines (multiple operations). But thanks anyway!

Accedi per commentare.

Community Treasure Hunt

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

Start Hunting!

Translated by