finddim

Find dimensions with specified label

Syntax

dim = finddim(X,label)

Description

dim = finddim(X,label) returns the dimensions in X that have the dimension label label. If the data format of X does not contain the dimension label label, dim is empty.

Examples

Obtain Dimension with Specified Labels

Create a formatted dlarray with some repeated dimension labels. Specify the dimension labels as 'TSSU'. The dlarray call reorders the labels, because it enforces the order 'SCBTU'. For more information about dimension labels, see Usage.

dlX = dlarray(randn(5,4,3,2),'TSSU');

Obtain the dimensions with the label 'T'.

dimT = finddim(dlX,'T')

dimT = 3

Obtain the dimensions with the label 'S'.

dimS = finddim(dlX,'S')

dimS = 1×2

     1     2

Obtain the dimensions with the label 'B'.

dimB = finddim(dlX,'B')

dimB =

  1x0 empty double row vector

Obtain the size of the dlX dimensions labeled 'S'.

SSize = size(dlX,finddim(dlX,'S'))

SSize = 1×2

     4     3

Input Arguments

X — Input dlarray

dlarray object

Input dlarray, specified as a dlarray object.

Example: X = dlarray(randn(3,4),'ST')

label — Single dimension label

'S' | 'C' | 'B' | 'T' | 'U'

Single dimension label, specified as one of the following dlarray dimension labels:

• S — Spatial

• C — Channel

• B — Batch observations

• T — Time or sequence

• U — Unspecified

Example: "C"

Data Types: char | string

Output Arguments

dim — Dimension

real vector

Dimension, returned as a real vector. If no label in the input array X matches label, dim is empty. So if X is unformatted, dim is empty.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

The label argument must be a compile-time constant.

GPU Code Generation

Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Usage notes and limitations:

The label argument must be a compile-time constant.

Version History

Introduced in R2019b