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length

Length of largest array dimension

Syntax

Description

example

L = length(X)returns the length of the largest array dimension inX. For vectors, the length is simply the number of elements. For arrays with more dimensions, the length ismax(size(X)). The length of an empty array is zero.

Examples

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Find the length of a uniformly spaced vector in the interval[5,10].

v = 5:10
v =1×65 6 7 8 9 10
L = length(v)
L = 6

Find the length of a 3-by-7 matrix of zeros.

X = zeros(3,7); L = length(X)
L = 7

Create a string array and compute its length, which is the number of elements in each row.

X = ["a""b""c";"d""e""f"]
X =2x3 string"a" "b" "c" "d" "e" "f"
L = length(X)
L = 3

Create a structure with fields forDayandMonth. Use thestructfunfunction to applylengthto each field.

S = struct('Day',[1 13 14 26],'Month',{{'Jan','Feb','Mar'}})
S =struct with fields:Day: [1 13 14 26] Month: {'Jan' 'Feb' 'Mar'}
L = structfun(@(field) length(field),S)
L =2×14 3

Input Arguments

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Input array, specified as a scalar, vector, matrix, or multidimensional array.

Complex Number Support:Yes

Tips

  • To find the number of characters in a string or character vector, use thestrlengthfunction.

  • lengthdoes not operate on tables. To examine the dimensions of a table, use theheight,width, orsizefunctions.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

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

HDL Code Generation
Generate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.

Introduced before R2006a