MATLAB Answers

what is difference between C=+A, C=A, C=unary(A)? All three provide same assignment of matrix A to C

1 view (last 30 days)
I cant understand the difference between C=+A, C=A, C=unary(A)?
All three provide same assignment of matrix A to C. Is there any difference among them

Accepted Answer

Chunru
Chunru on 27 Jul 2021
Edited: Chunru on 29 Jul 2021
C=+A;
C = uplus(A) is an alternate way to execute +A, but is rarely umeased. It enables operator overloading for classes.
So depending on class of A, +A or uplus(A) may have different meaning.
C = A; This is just an assignment.
[Update based on comments below]
For assignment:
  • C = A; This is assiment only. MATLAB will do a lazy copying (pointer to A) and only do the real data copying when C is changed later.
  • C = +A or C=uplus(A); +A and uplus(A) is the expression or function that involves A. The meaning of + and uplus is class dependent. The expression and function need to be evaluated first before assignment. The evaluation results is assigned to C (data copying is necessary).
The meaning of +/upluse:
  • For numerical data types like double/single/etc, this will have no effect of the results.
  • For logical and char, +/upluse has the effect of operator overloading. The result is of numerical data type double.
As function input arguments:
  • +A and uplus(A) is the expression, as in table(+A)
In addition, it is possible (but rarely) for user to do the operater overloading of +/uplus.
  5 Comments
Steven Lord
Steven Lord on 28 Jul 2021
That's true, I'd forgotten about char. I guess I was a little more tired than I thought when I wrote that response.

Sign in to comment.

Products


Release

R2021a

Community Treasure Hunt

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

Start Hunting!

Translated by