All Questions
207 questions
0
votes
0
answers
44
views
Find the page in a 3D matrix that is closest to a given matrix
One can easily concatenate (stack up) four arrays by using:
B = cat(3, A, A, A, A); % here A is 2-dimensional M x N matrix and B is 3-dimensional M x N x 4 stack
How is it possible to concatenate (...
3
votes
1
answer
97
views
How to make a function work with different sized meshgrid/linspace inputs
I have a a function called [U,V,W] = my_function(x,y,z) which takes grid vectors as inputs and calculates some outputs evaluated at those grid points. There are N grid points in total.
The problem is ...
3
votes
1
answer
50
views
A universal algorithm for filling an array [duplicate]
I have a code and it works for 3 dimensions, but I want to be able to specify the number of dimensions dynamically. There is a function nchoosek, but it creates an array of non-repeating elements.
...
3
votes
1
answer
61
views
Inserting rows into linear-indexed, collapsed matrix
Say we have an n-dimensional logical array P describing whether certain positions in an n-space are "set" or "cleared" (with respect to some attribute), and these positions are ...
0
votes
1
answer
111
views
Interactive plot to change array values (MATLAB)
N = 500;
pattern = zeros(N,N);
grid on
plot(pattern)
% gets coordinates of modified cells
[x,y] = ginput;
% convert coordinates to integers
X = uint8(x);
Y = uint8(y);
% convert (X,Y) into linear ...
0
votes
1
answer
169
views
Understanding a multidimensional array in Matlab
I have a figure and I am trying to understand it in Matlab.
I = imread('frame.png');
x = I(:,:,1);
y = I(:,:,2);
z = I(:,:,3);
In the Matlab workspace, the size of I is 480x640x3. I assume that this ...
0
votes
1
answer
2k
views
How to solve "Conversion to double from struct is not possible" error in Matlab
I'm trying to run the code below but I keep getting the "Conversion to double from struct is not possible" error over and over. I'd really appreciate it if you could help me with what's ...
1
vote
1
answer
48
views
Analog to .* for tensor/ vector multiplications in matlab
I am generalizing a 1-D numerical method to 2-D and have run into an inconvenience. I was previously scaling each row in an array by using b.*A, where b is a (nx1) vector and A is an (nxm) array.
Is ...
1
vote
1
answer
75
views
Difference of elements of an array with all element of another array in MATLAB
Suppose I have two arrays of different sizes. Say A=[10;12;13;17;18]; and B=[20;22;23;17;26;30;32];. The output, C will be as follows:
[10, 8, 7, 3, 2;
12, 10, 9, 5, 4;
13, 11, 10, 6, ...
-1
votes
1
answer
49
views
Removing rows by index from arrays in matlab [duplicate]
I have an array 2500*30 elements (its type is "single") and I need to remove several rows that I know the index. For example:
duplicate_ids = [1,4:8,11,859,866,1673,2157,2187,2188,2194,2195];...
1
vote
1
answer
64
views
Create 3 3D arrays from 3 1D arrays in Python
I would like to find a way to mimic MATLAB's ndarray in Python (very different ndarry function!)
so if I have 3 1D arrays, say i = 0:10, j = 0:11, k = 0:12, I would like to create 3 3D arrays,
I, J ...
3
votes
2
answers
121
views
MATLAB: Iterating through multiple double arrays to find min/max value
I'm currently trying to find the min/max value of 5 different 2x1 arrays of doubles on Matlab. I wrote a function below that works, returning the min and max values from all 5 arrays listed. However, ...
-1
votes
1
answer
113
views
MATLAB for loop to multiple columns
I have the following block of code that I developed in MATLAB to calculate RSI.
%RSI Calculation
n = [14:2:18];
for i = 1:n
gainC = diff(ABC).*((diff(ABC))> 0);
lossC = -(diff(ABC)).*((...
0
votes
0
answers
218
views
How can I convert this MATLAB cell array into a Numpy file/Python array?
This is what my variable, call it A, looks like in MATLAB (only 10 cells):
Then, this is what the first cell 1,1 looks like (goes on for 20 cells):
Then, this is what the first cell of that image ...
4
votes
2
answers
430
views
Does MATLAB support truly 1d arrays?
It would really help me reason about my MATLAB code if I didn't have to worry about accidental 2d operations. For instance, if I want to do element-wise multiplication of 1d arrays, but one is a row ...