A question about the efficiency of matrix multiplication in MATLAB.
Matlab was built to do matrix math first, with the highly optimized LAPACK library at its heart. That's what it's using for case...

8ヶ月 前 | 0

How can I average same-calendar-month returns over the prior 20-year period?
This is a complex question. I would answer your questions with a cell array of tables, and a whole lot of untested (because I d...

8ヶ月 前 | 0

| 採用済み

How do i write a line to display all the values that didn't meet the requirement
SigmaAp = 5; SigmaAx = randi(9,5,1) idxs = find(SigmaAx>SigmaAp) disp('Values over the limit:');disp(SigmaAx(idxs))

8ヶ月 前 | 0

| 採用済み

How to read GSI (text) file?
A = readlines('Example_of_GSI.txt'); parsed = split(A).strip('*'); Does that break it down enough for you to work with?

8ヶ月 前 | 0

| 採用済み

I need to find a pattern in a column
A = readmatrix('test.xlsx'); count = 0; for idx = 1:numel(A)-34 if sum(A(idx:idx+34)) == 0 count = count+1; ...

8ヶ月 前 | 0

| 採用済み

Livescript results in incorrect Math output
The commented-out line is: lambda_j + 2*rp*max(subs(g1,[x1;x2],x), -lambda_j/(2*rp)) lambda_j is 1. The second term (which use...

8ヶ月 前 | 0

Why shift, take absolute value and perform log transform to the frequency spectrum of an image obtained by fft2?
take the absolute value The log of a negative number is undefined, which would make for a boring image. apply a log transforma...

8ヶ月 前 | 0

Store values from a for loop in matrix and plot them.
You need an index to keep track of your loop iterations. You can do this one of two ways: idx = 0 for Prc = Prc=7:1:27 idx = ...

8ヶ月 前 | 0

| 採用済み

How to draw a surface starting from a 3 column vector X, Y, Z with no regular grid on X, Y ?
Another useful function is griddata

8ヶ月 前 | 0

changing the time zone for two datetime objects then comparing them
t.Date3.TimeZone = 'Asia/Dubai'; d.date.TimeZone = 'Asia/Dubai'; Works for me.

8ヶ月 前 | 0

convert python code to MATLAB
With Mie.py in your Matlab path and pyenv set up correctly, do: mie = struct(py.Mie.MieQ(1.525+0.0011j,450,300,pyargs('asDict',...

8ヶ月 前 | 0

Contour plot omitting certain points
If it bothers you, you can set caxis(min_lim,max_lim). You can include more levels by indicating the number in the function cal...

8ヶ月 前 | 0

| 採用済み

Increase the height (size) of subplots
If you have 2019b or newer, you can use a tiledlayout. It doesn't really show here, but there's a difference. https://www.mathw...

8ヶ月 前 | 0

How can I identify only the first or first two local minima from "islocalmin" and then display it in a table on a plot?
% Find the index of the first minimum TF=find(islocalmin(VarName2),1); % Get the values for the lower and upper curves lowerV...

8ヶ月 前 | 0

| 採用済み

How to remove outliers in a 3D surface
I would recommend trying the "clean outlier data" task in the live editor, after sorting the data: T = sortrows(T,1); % Sort by...

8ヶ月 前 | 0

how can i save the even index to a matrix 2:5 using for loop
z=randi([1 10],5,10) newmatrix = []; for i=1:5 if(mod(i,2)==0) for j=1:10 if(mod(j,2)==0) % ...

8ヶ月 前 | 1

How to make a contour plot with incomplete z data?
As far as I understand, you'll need a rectangular array representing the grid of intensity values. If your grid is square and yo...

8ヶ月 前 | 0

my while statement wont work
It looks like you need to reset Err to 1 after a loop completes.

8ヶ月 前 | 0

Question about finding the number of times an element appears in an array
A = randi(9,2) A(:) formats A in a column vector. A(:) A(:)==c compares the column to each element of c (possible because th...

8ヶ月 前 | 0

| 採用済み

Find the standard error of the mean for each column in a matrix containing NaN and numerical values
That's a 4x4 matrix, not 5x4. The default behavior or nanmean and nanstd is to give you the statistic for each column. Taking t...

8ヶ月 前 | 0

| 採用済み

Switch and Case using radio buttons
The tag is a string (technically a char vector). Include the quotes. case 'b1' and case 'b2'

8ヶ月 前 | 0

| 採用済み

how to Expand the plot line in a function
The default x interval for fplot is [-5 5]. You can change it with the xinterval argument: fplot(y,[0,130]) You don't need an ...

8ヶ月 前 | 0

| 採用済み

renaming a variable, or creating a dynamic variable name
If the cells are really holding Matlab tables, you could assign the sampleNames as table Descriptions: for idx = 1:n data{...

8ヶ月 前 | 0

| 採用済み

Cannot install matlab on ubuntu 18.04
Try: xhost +SI:localuser:root sudo ./install https://www.mathworks.com/matlabcentral/answers/518584-how-do-i-install-on-ubunt...

8ヶ月 前 | 10

| 採用済み

Extraction of non zero rows from a matrix
A = [magic(3);zeros(1,3)] svp = A~=0 extracted = reshape(A(svp),[],3) If there is a possibiity of finding zeros in a nonzerow...

8ヶ月 前 | 0

| 採用済み

Replace negative values with zero and values above 1 with 1, using loop in a 8760 x 1000 matrix
Is there a reason you want to do it in a loop? Matlab excels at vectorized operations. The following is simpler and faster than...

8ヶ月 前 | 0

| 採用済み

Formatting the fit function
epsilon = (0:0.2:5)'; load = 2*exp(-0.2*epsilon) + 0.5*randn(size(epsilon)); fitting = fit(epsilon, load, 'poly2'); plots = p...

8ヶ月 前 | 0

| 採用済み

Plotting a contour of a function with one input variable
exes = linspace(-2*pi,2*pi); whys = exes; theta = [exes',whys']; takeOneInput(theta) You can pack as much as you want into a...

8ヶ月 前 | 0

How exactly does the gradient function work when applying it to an image?
If you type open gradient, in the Command window, the relevant code is: % Take forward differences on left and right edges if ...

8ヶ月 前 | 0

| 採用済み

Merging row elements into single numbers
Edit: Use Star Strider's answer. It's faster. C = [3 4 5 6 7 9 1 5 8] C = double(string(C).join(''))

8ヶ月 前 | 1

| 採用済み