~ means NOT
so *isempty* tells you if the vector is empty and *~isempty* tells you if the vector is _not_ empty. Answer from Adam on mathworks.com
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mathworks.com › matlab › language fundamentals › matrices and arrays
isempty - Determine whether array is empty - MATLAB
In MATLAB®, an empty array has at least one dimension length equal to zero. An array containing missing values, such as NaN or <undefined>, is not necessarily empty.
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mathworks.com › system identification toolbox
isempty - Determine whether dynamic system model is empty - MATLAB
The isempty command returns 1 because the system does not have any outputs. Similarly, isempty returns 1 for an empty transfer function. ... Now create a state-space model with 1 input and 1 output. In this example, specify the A, B, C, and D matrices as 1, 2, 3, and 4, respectively. ... Determine whether sys2 is empty. ... The command returns 0 because the system has inputs and outputs. ... Run the command by entering it in the MATLAB Command Window.
Why is an empty string not empty? isempty('') returns true, but isempty("") returns false
Why is an empty string not empty? ... Learn more about string, empty MATLAB More on mathworks.com
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January 19, 2018How to check if an array is empty without using any built in functions
How to check if an array is empty without using... Learn more about matrix array More on mathworks.com
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September 4, 2021How to write while a set Q is not empty do the following in matlab?
How to write while a set Q is not empty do the... Learn more about while loop, loop, matlab function More on mathworks.com
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February 17, 2020How can I use an empty matrix in a logical if statement?
Is there any way to use an if statement that will run only if u is an empty 8x0 matrix? (And yes, I know that eval + num2str is frowned upon, I didn't write that part! Apologies in advance!) ... Sign in to comment. Sign in to answer this question. ... https://www.mathworks.com/matlabcentral/ans... More on mathworks.com
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January 22, 2014MathWorks
mathworks.com › matlab › software development tools › testing frameworks › write unit tests
matlab.unittest.constraints.IsEmpty - Test if value is empty - MATLAB
The test fails because the cell array is not empty. ... Verification failed. --------------------- Framework Diagnostic: --------------------- IsEmpty failed. --> The value must be empty. --> The value has a size of [1 3]. Actual Value: 1×3 cell array {0×0 double} {0×0 double} {0×0 double} Test an empty test suite. The test passes. ... Verification passed. ... matlab.unittest.constraints.HasElementCount | matlab.unittest.constraints.HasLength | matlab.unittest.constraints.HasSize | matlab.unittest.constraints.IsScalar | verifyEmpty | verifyThat | isempty
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mathworks.com › matlabcentral › answers › 378004-why-is-an-empty-string-not-empty-isempty-returns-true-but-isempty-returns-false
Why is an empty string not empty? isempty('') returns true, but isempty("") returns false - MATLAB Answers - MATLAB Central
January 19, 2018 - As of R2016b, "" is a string object, not an empty array. The problem is that code written prior to R2016b never had to test for input of "" , so that code now behaves incorrectly if someone passes is an empty double-quoted string. ... https://www.mathworks.com/matlabcentral/answers/378004-why-is-an-empty-string-not-empty-isempty-returns-true-but-isempty-returns-false#comment_526453
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mathworks.com › matlabcentral › answers › 506040-how-to-write-while-a-set-q-is-not-empty-do-the-following-in-matlab
How to write while a set Q is not empty do the following in matlab? - MATLAB Answers - MATLAB Central
February 17, 2020 - I want to write this algorithm in matlab: while Q , do - - - end(do)
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mathworks.com › matlab › programming › classes › define classes › properties
mustBeNonempty - Validate that value is nonempty - MATLAB
Use mustBeNonempty to validate that the input is not empty.
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mathworks.com › matlab › software development tools › testing frameworks › write unit tests
matlab.unittest.qualifications.Verifiable.verifyNotEmpty - Verify value is not empty - MATLAB
This MATLAB function verifies that actual is a nonempty MATLAB array.
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mathworks.com › matlab › language fundamentals › data types › characters and strings
Test for Empty Strings and Missing Values - MATLAB & Simulink
String arrays can contain both empty strings and missing values. Empty strings contain zero characters and display as double quotes with nothing between them (""). You can determine if a string is an empty string using the == operator. The empty string is a substring of every other string.
Top answer 1 of 2
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Use CELLFUN
%# find empty cells
emptyCells = cellfun(@isempty,a);
%# remove empty cells
a(emptyCells) = [];
Note: a(i)==[] won't work. If you want to know whether the the i-th cell is empty, you have to use curly brackets to access the content of the cell. Also, ==[] evaluates to empty, instead of true/false, so you should use the command isempty instead. In short: a(i)==[] should be rewritten as isempty(a{i}).
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All above mentioned answers are incorrect, because in my case when i used them, they removed empty cells and then all elements of my cell array situated in a row manner instead of preserving their actual shape. In fact after using this kind of approach your cell array elements tend to be a row cell vector.
I have found this approach which works correctly in my case.
source : https://groups.google.com/forum/#!topic/comp.softsys.matlab/p3NX0fI6u90
approach:
myCellARRAY(all(cellfun(@isempty,myCellARRAY),2), : ) = [];
Quora
quora.com › How-do-you-check-if-a-variable-is-empty-in-MATLAB
How to check if a variable is empty in MATLAB - Quora
Answer: [code]>> doc isempty [/code]Note the distinction in MATLAB between a variable that exists, but has no meaningful value (apart from the null matrix), and a variable that doesn’t exist at all: [code]>> doc exist >> doc clear >> doc clearvars [/code]An empty variable is often a useful signa...
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mathworks.com › matlab › programming › classes › construct and work with object arrays
empty - Create empty array of specified class - MATLAB
MATLAB fills the other elements of the array with the default value of the array type, which for uint8 is 0. ... To initialize a nonempty array, use a function such as zeros or ones to fill the array with initial values. MATLAB does not have a null value, so all nonempty arrays must have values ...
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mathworks.com › matlab › language fundamentals › matrices and arrays
Empty Arrays - MATLAB & Simulink
An empty array in MATLAB® is an array that has no elements. Empty arrays are useful for representing the concept of "nothing" in programming. Empty arrays have specific dimensions, and at least one of those dimensions is 0.
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mathworks.com › matlabcentral › answers › 2026644-how-do-i-find-out-a-struct-is-empty
How do I find out a struct is empty? - MATLAB Answers - MATLAB Central
September 27, 2023 - is_empty_struct = isempty(A), has_no_fields = isempty(fieldnames(A)) ... https://www.mathworks.com/matlabcentral/answers/2026644-how-do-i-find-out-a-struct-is-empty#comment_2903819
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mathworks.com › matlabcentral › answers › 797582-isempty-function-does-not-work-for-me
isempty function does not work for me - MATLAB Answers - MATLAB Central
April 9, 2021 - https://www.mathworks.com/matlabcentral/answers/797582-isempty-function-does-not-work-for-me#comment_1450197 ... That is correct. ... The char vector 'x' is not empty.