1,045 questions
5
votes
2
answers
94
views
How to pass cell indexing as an input argument to a function, such that cell inside the function can use the indexing directly?
I am wondering if we can pass cell indexing as an input argument to a function, such that a cell inside the function can parse it.
For example, given a cell like x = num2cell(reshape(1:24, [2,3,4])), ...
- 106k
2
votes
2
answers
68
views
How to effciently add a field of the same repeated value to a struct array
I have a non-scalar struct array. For example
S=struct;
S(1).f1='a';
S(2).f1='b';
How do I add a field .f2 to S for the same value 1 efficiently? such that S becomes a struct with
S(1).f2=1;
S(2).f2=...
- 10.1k
2
votes
3
answers
101
views
how to sum cells/ struct in matlab
I am trying to add vertically the lists of a database like DB (see below) contained in a cell.
DB={ {[11 12]} {[13 14]} {[15 16]} {[17 18]} {[19 20]};
{[21 22]} {[23 24]} {[25 26]} {[27 28]} {[...
1
vote
1
answer
492
views
<Missing> Values in Cell Arrays Created from Matlab readcell()
I am uploading data from an Excel file which was provided in a specific format, for which a minimum reproducible example is shown below:
I am trying to save each column into an array, using the ...
- 141
2
votes
2
answers
357
views
extracting a row from a cell-array
I have a cell-array in which contains some information on how to process some data, like the following:
C = [
{{1 2 3} true 0 0 5 false}; ...
{{2 3 4} true 0 0 3 false} ...
]
How can I ...
- 180
1
vote
2
answers
183
views
Matlab cellfun, how to apply indexing to strings on each element?
I'm having trouble indexing into strings contained in a cell array using the cellfun function. I have a cell array with strings of various contents, and I'm trying to extract the numbers between the ...
- 195
0
votes
1
answer
31
views
Populate Every other Element of Array with Function Handle MATLAB
I have the following function:
function F = farray (f,N)
F = {@(t) zeros(N,1)};
for i=1:N
if mod(i,2)==0
F{i}=f(t);
end
end
F = cell2mat(F);
end
f is a function ...
0
votes
1
answer
112
views
transferring data between python and MATLAB: how to deal with list of lists?
I did this post in Mathwork as well. But I guess I will benefit also asking it here.
Here is a link to my mathwork community post.
https://www.mathworks.com/matlabcentral/answers/2104821-load-save-...
- 1
1
vote
1
answer
61
views
Convert Cell Array of Symbolic Functions to Double Array of Symbolic Functions MATLAB
I have the following:
syms x;
F = {3*x,2*x,x};
I would like to make F the following array G:
G = [3*x,2*x,x];
To do this, I have tried this:
G = double(F);
and this:
G = double([F{:}]).';
Neither ...
0
votes
2
answers
121
views
Is there a functional form in Matlab to get the same result as A{:}?
I understand this is a classic question and some aspects of it have been answered before, for instance here: How can I index a MATLAB array returned by a function without first assigning it to a local ...
- 11
2
votes
2
answers
122
views
Extractig data from cell array
In this MWE, I generate dis (x, y, z displacements for nodes and increments), I then need to extract separately the displacements
clear
k=0;
% ignore following, this is just to buils dis
for node=1:20
...
- 295
1
vote
0
answers
101
views
Pass Function Handle to ODE45 in Matrix
I'm trying to use ode45 to predict the behavior of the following system:
I'm getting the following error with my Force matrix F:
Since the forcing function changes with time, I made it a function ...
3
votes
2
answers
130
views
How to fix this error extracting empty structure fields from a cell array when using cellfun()
I have a cell array in Matlab, with each cell representing a financial transaction as a structure object (the cell array is earlier imported from a json file).
Here is an example to create a test set ...
- 785
0
votes
1
answer
56
views
How to create parametrized matrix
I would like to create parametrized matrix with given relationship between arguments like this:
B= @(A) [1*A(1), 2*A(2), 3*A(3), 4*A(4)];
But matrix is huge and cannot be created by constant ...
- 195
0
votes
1
answer
44
views
Creating a cell array with 2 rows; 1st row for characters and 2nd for their related 5 bits using dec2bin function in matlab
I am trying to make a 2*32 cell array in matlab. The first row are the characters 'a' to 'z' , space, period, comma, exclamation Point, semicolon and quotation (32 chars).
The second row must be '...
- 15
0
votes
2
answers
2k
views
Why does cell2mat convert a cell array into a matrix of characters, instead of a matrix of cell contents?
I have this cell array
>> FooCellArray
FooCellArray =
1×7 cell array
Columns 1 through 4
{'Foo1'} {'Foo2'} {'Foo3'} {'Foo4'}
Columns 5 through 7
{'Foo5'} {'Foo6'} ...
- 20.1k
2
votes
2
answers
158
views
Deleting consecutive and non-consecutive columns from a cell array in Matlab
I'm trying to delete multiple consecutive and non-consecutive columns from a 80-column, 1-row cell array mycells. My question is: what's the correct indexing of a vector of columns in Matlab?
What I ...
- 351
2
votes
1
answer
2k
views
MATLAB Search Within a Cell Array of Cells
Setup:
I have a 21 x 3 cell array.
The first 2 columns are USUALLY strings or char arrays, but could be 1xn cells of strings or char arrays (if there are multiple alternate strings that mean the same ...
- 1,664
1
vote
1
answer
160
views
Creating a loop in MATLAB to split up a list of sentences by a delimiter
I want to be able to run a loop through my current code. I have a cell array with 423 cells. Each cell is a long string of smaller strings that I am trying to separate by the delimiter (;) and I want ...
- 61
2
votes
1
answer
43
views
Removing Measurement Units from Cell Array
I am trying to remove the units out of a column of cell array data i.e.:
cArray =
time temp
2022-05-10 20:19:43 '167 °F'
2022-05-10 20:19:53 '173 °F'
2022-05-10 20:20:03 '177 °F'
......
- 41
1
vote
1
answer
4k
views
Concatenate cell array in MATLAB
In Matlab you can concatenate arrays by saying:
a=[];
a=[a,1];
How do you do something similar with a cell array?
a={};
a={a,'asd'};
The code above keeps on nesting cells within cells. I just want ...
- 155
0
votes
2
answers
130
views
Group data in a cell array
I have the following data:
Names={A1 A2 B1 B2 C1 C2 C3}
Doserate=(2.2 3.4 6.4 3.4 2.3 4.5 7.5)
Time=(5 7.8 9 3.5 10.2 5.6 7.8)
The order of Doserate and Time is such they correspond to Names. I would ...
- 67
0
votes
1
answer
67
views
How to store every element of a cell array in a separate folders?
I have a problem assigning and storing data to subfolders. I have one folder let's say a new folder, and I created 6 subfolders based on the size of a cell array. Now I want to save every element of ...
0
votes
1
answer
51
views
Assign same number of elements to the column data based on number of elements (each row) of the other column
I have two column data, where first column contains "Number of Elements" and the second column contains "Stages" data. I want to assign the same number of data elements of "...
- 25
0
votes
2
answers
2k
views
How to append an empty array to a cell array
How do you append an empty array to a (non-empty) cell array?
For example, starting with
c={[1],[2]}
desire
c={[1],[2],[]}
Concatenation would remove the empty array whether it is double, char or ...
- 10.1k
1
vote
1
answer
345
views
How to create all permutations of a 2-column cell-array?
I created a cell array of shape m x 2, each element of which is a matrix of shape d x d.
For example like this:
A = cell(8, 2);
for row = 1:8
for col = 1:2
A{row, col} = rand(3, 3);
...
- 445
1
vote
3
answers
160
views
Matlab: non-integers or numbers below 1 as indices; numbers as field names
Matlab has limitations in terms of how things can be numbered/indexed:
Arrays and cell arrays require indices that are natural
numbers (with exceptions that are discouraged and not more general).
...
- 2,964
1
vote
1
answer
1k
views
Using python to create a .mat file with a cell array in it
I'm trying to create a mat file with a cell it it. I tried to apply some solutions I found on the internet but non of them worked.
The code I'm wishing to have at the end is something like that:
...
- 65
1
vote
3
answers
247
views
Matlab: What's the most efficient approach to parse a large table or cell array with regexp when sometimes there is no match?
I am working with a messy manually maintained "database" that has a column containing a string with name,value pairs. I am trying to parse the entire column with regexp to pull out the ...
- 33
0
votes
1
answer
109
views
How to convert 1d array of chars from CSV to 2d cell array in Matlab
I have a function I cannot change in Matlab that converts CSV file to a 1d array of chars.
This is an example of what it looks like:
array_o_chars = ['1' 'd' ',' ' ' 'a' 'r' 'r' 'a' 'y' '\n' 'o' 'f' ',...
- 128
0
votes
0
answers
310
views
cell2mat produces wrong output size
I have a cell matrix with size 32x32 where each cell is an 8x8 matrix and all values are floats. I use DCT to each 8x8 cell and after that I assign each matrix to another empty cell matrix. So, the ...
- 21
0
votes
1
answer
1k
views
Array values to cells
I have google script for changing text in rows. Problem after text modification is that I do not know how to save array values to cells in second sheet.
// Array to cells
function ...
- 21
0
votes
1
answer
216
views
R equivalent to permuting array dimensions permute(A, dimorder) in Matlab
I am looking for an equivalent of permute(A,dimorder) from Matlab, in order to convert some Matlab code to R.
A loop entails a line that looks something like this:
x = permute(a{i}(b(i,ii),:,:,:,:,:),[...
0
votes
1
answer
76
views
python3 - after successfully reading CSV file into 2D Arrary - how to print a single cell by index?
I want to read a CSV File (filled in by temperature sensors) by python3.
Reading CSV File into array works fine. Printing a single cell by index fails. Please help for the right line of code.
This is ...
- 51
0
votes
2
answers
339
views
How to assign indexes to a function handle?
I'm trying to approximate the integral of the functions "fun_1" and "fun_2" over the given region. In the case of one single "f" it seems ok. But I want to use a vector &...
0
votes
0
answers
218
views
MATLAB Cell Array - Replacing Numbers in Different Columns with Strings
I am working in Matlab.
I created a matrix and then a cell array based on that matrix:
A = randi([1 5], 5, 5);
B = num2cell(A);
I want to replace the numbers in B with different strings based on A's ...
- 1
0
votes
1
answer
149
views
counting most commonly used words across thousands of text files using Octave
I've accumulated a list of over 10,000 text files in Octave. I've got a function which cleans up the contents of each files, normalizing things in various ways (lowercase, reducing repeated whitespace,...
- 2,877
0
votes
0
answers
64
views
How can I convert a 2-D cell array to a 3-D cell array in matlab
Each cell is a single element (I'm not storing arrays larger than 1x1 in a cell array... I'm using a cell array to hold both numbers and characters).
The cell array is 32x3822x1 and stores information ...
2
votes
2
answers
277
views
Why is the cell array structure in Matlab not behaving well and keep constructing vectors?
Let's say I have two simple vectors;
vec1=[1,2,3];
vec2=[4,5,6];
Now I make a cell array from them.
cellArray1={vec1,vec2}
If I want to create a 2x3 numerical array, it is simple.
[vec1;vec2]
%or
[...
-1
votes
2
answers
1k
views
Matlab - Accessing Table fields from a table in cell array
I have problems accessing a column from a table in a cell array.
I have a matlab function looking like this:
function [tables, rthTables, iGateTables, lastValueTables] = dataEinlesen(~, tcoFiles)
...
- 49
1
vote
1
answer
129
views
Repmat in Matlab to replicate specific elements
I have the following lines of code where I find an event "41" in my cell array called Events (minimal example of this array included below) and the lines of code allow me to add 8 events ...
- 549
0
votes
1
answer
169
views
Aligning multiple arrays in a cell array by prepending/postpending NaNs
I am trying to align arrays within a cell-array while prepending/postpending NaNs to match the size of arrays like this for example:
%Setting up data
A = [0.01 0.02 0.03 0.01 0.60 0.90 -1.02];
B = [0....
- 217
0
votes
2
answers
202
views
Convert cell string with commas and spaces to vector
I tried to convert the cell x:
x(1,:) = {'35,35, ,35'};
x(2,:) = {'40,40,30,40'};
x(3,:) = {'10, , ,'};
to a matrix with:
R = cell2mat(cellfun(@str2num,x,'un',0));
but the outcome omits the first ...
- 1,511
0
votes
1
answer
116
views
Pre-Allocating Single Cell's Memory
I am writing a code and would like to know how to pre-allocate the memory for a single cell. I understand that one can easily pre-allocate an array of cells, but this isn't what I'm looking for.
My ...
- 61
0
votes
1
answer
382
views
How to find an matching element (either number or string) in a multi level cell?
I am trying to search a cell of cell arrays for a matching number (for example, 2) or string ('text'). Example for a cell:
A = {1 {2; 3};4 {5 'text' 7;8 9 10}};
There is similar question. However, ...
- 1
0
votes
1
answer
264
views
Removing duplicate strings from a nested cell array
I have a 1x234 cell array called tmp from which I want to delete all duplicates. Some elements of tmp can be:
tmp{1, 3} -> 'Ro'
tmp{1, 167}{1, 1} -> 'Ro'
tmp{1, 167}{1, 2} -> 'CvF'
Of the ...
- 3
0
votes
2
answers
453
views
Octave: How to assign the right dimensionality to an existing cell array to avoid "error: =: nonconformant arguments (op1 is 2x2x2, op2 is 2x2x2)"?
I am a beginner at Octave, that is why I will share something too obvious for the most.
cell_arr = cell(2,2,2);
cell_arr(2,2,2) = cell(2,2,2);
error: =: nonconformant arguments (op1 is 2x2x2, op2 is ...
- 9,962
1
vote
2
answers
1k
views
Cell Array String from Matlab to Python
I have a .mat dataset obtained from Matlab that have some data, including an 1920x1 Cell Array String stored as follow:
"sample1"
"sample2"
"sample3"
I need to import it ...
- 11
0
votes
1
answer
238
views
How to extract one column from Matlab matrix?
I have the following code:
N = 10;
params = cell(N-3,4);
step = 1;
for i = 3 : N-1
% Calibrate the camera
[cameraParams, imagesUsed, estimationErrors] = estimateCameraParameters(...
- 201
0
votes
1
answer
160
views
Extracting arrays from array
I am currently working on machine learning, and as so I have an array in which the first column is the data and the second column is the label. Data was originally a cell array from Matlab (Not sure ...
- 3