Is there a function Is_array in matlab ?

I may be a newbie in matlab have a small problem with a libray in matlab : I don't know if there a function is_array in matlab.

Error in tt_tensor (line 183) if is_array(varargin{1})

My code worked somme weeks ago but didn't work since yesterday.

If someone could help me, I will be gratfull.

Answer 1

[KALYAN ACHARJYA]

No, there is no "Is_array" inbuilt function in MATLAB, there is "isvector" inbuilt function

isvector(data) returns logical 1 (true) if data is a vector. Otherwise, it returns logical 0 (false).

More: There is "uiarray" function, this function is used primarily for creating UI controls of demos of the toolbox.

Deatail, please check

>> help uiarray

[Mohamed Anwar ABOUABDALLAH]

Hi KALYAN,

Thank you for the answer. The problem is that i'm using a function tt-factor() from tt-toolbox library. And the problem is that I can't manipulate this function because it needs is_array().

So probably function didn't exist in matlab, but it exist in c++, so can I use std library cpp in matlab ?

[Mohamed Anwar ABOUABDALLAH]

Finaly I decide to use the comnation isvector(size(x)) instead of is array.

Thanks for the help.

[KALYAN ACHARJYA]

Welcome

:)

[Zeng]

I encounter the same problem when using TT-toolbox ( https://github.com/oseledets/TT-Toolbox ). I guess maybe there is a time when is_array is usable in matlab but now we can only use ismatrix as a substitute? Since array in python behave just same as matrix, and in matlab we always call a n-dimensional thing a matrix. Just curious whether this is an explanation.

[Walter Roberson]

I doubt that there was ever a function named is_array in the remote past. Functions named with an underscore is not Mathworks style for core functions; Mathworks would have used isarray

[Stephen23]

"in matlab we always call a n-dimensional thing a matrix"

No, we never call a n-dimensional thing a matrix. The MATLAB documentation states "All MATLAB variables are multidimensional arrays, no matter what type of data. A matrix is a two-dimensional array often used for linear algebra."

source: https://www.mathworks.com/help/matlab/matrices-and-arrays.html

So a matrix is just an array where all dimensions >2 are scalar. This matches exactly the definition used by ISMATRIX, which states that "A matrix is a two-dimensional array that has a size of m-by-n, where m and n are nonnegative integers."

source: https://www.mathworks.com/help/matlab/ref/double.ismatrix.html

Using an incorrect definition of matrix is likely to caus a lot of confusion, as your comment indicates.