Community Profile

photo

Joel Lynch


Last seen: 4 días hace Con actividad desde 2021

Statistics

All
  • Thankful Level 2
  • Knowledgeable Level 3
  • MATLAB Mini Hack Participant
  • Personal Best Downloads Level 2
  • Thankful Level 1
  • Knowledgeable Level 2
  • First Answer
  • First Review
  • GitHub Submissions Level 2
  • Explorer
  • First Submission

Ver insignias

Content Feed

Ver por

Pregunta


Without resorting to FEX/MEX, can the overhead of repeated calls to sparse() be avoided with operations on I, J, V directly?
I have a time-marching problem bottlenecked by matrix multiplication , where the sparse matrix is the sum of many time-independ...

6 meses hace | 1 respuesta | 0

1

respuesta

Respondida
fmincon/multistart won't debug/display errors in OutputFcn
I figured out the issue, 'OutputFcn' must be added in Multistart, not fmincon. This also means using different syntax for the ca...

10 meses hace | 0

| aceptada

Pregunta


fmincon/multistart won't debug/display errors in OutputFcn
If "x=b" is uncommented, the code still runs and does not break on error or display the line number. This means debugging a mor...

10 meses hace | 1 respuesta | 0

1

respuesta

Pregunta


Is there a better way to initialize the DataTipTemplate field in primitive objects?
Problem: Creating a Chart Object as in Plot() initializes a DataTipTemplate field in the resulting handle. p = plot(0,0); p...

alrededor de 1 año hace | 1 respuesta | 0

1

respuesta

Canal


mychannel
test

más de 1 año hace

Pregunta


Why do logical indices implicitly reshape? Is there a workaround?
I've encountered this several times, and it always bothers me. Say for example I want to sum each row of matrix A, for values le...

más de 1 año hace | 1 respuesta | 0

1

respuesta

Pregunta


When using "Pause on Warning/Error," is there a way to avoid breaking into built-in functions?
For example, a bad set of data when calling "fit" breaks into a function called "curvefit.attention/Warning/throw": Warning: Eq...

más de 1 año hace | 1 respuesta | 1

1

respuesta

Respondida
Box Plots for Vectors of Varying Length
The proximate error is that the symbols around the year-range string ‘1931-1960’ are not apostrophes, so MATLAB doesn't know w...

más de 1 año hace | 0

| aceptada

Respondida
Mesh Grid of a 3d array
So this may be due to confusion about how mesh() works. Mesh produces a 2D surface in a 3D volume, with the Z-axis being the val...

más de 1 año hace | 0

| aceptada

Respondida
Run "if" logic on a row
The trick is to recognize that you can use & / | (and/or) to chain multiple logical operations together. In this case, you can g...

más de 1 año hace | 0

| aceptada

Respondida
Solve the generalized form of the Poisson equation
I don't get an error when running your code with MATLAB version 2019b, but the bigger problem you have is that your method will ...

más de 1 año hace | 0

| aceptada

Respondida
How to plot a matrix within a matrix?
In terms of organizing the data, the simplest approach is to create two matricies for stiffness and deflection that have two dim...

más de 1 año hace | 1

| aceptada

Enviada


ternary_plots
MATLAB package for creating ternary plots. Based loosely on 7210-ternary-plots by Ulrich Theune.

más de 1 año hace | 31 descargas |

Thumbnail

Respondida
set xticks by calculation but also force 0 to be displayed
set(gca,’XTick’,array_of_values)

más de 1 año hace | 0

Respondida
Function for telling if a function is unique and how many solutions it has.
".p" files are purposefully obfuscated, so you cannot copy the code, suggesting your instructor does not want you to use someone...

más de 1 año hace | 0

| aceptada

Respondida
Why do I get 'Out of Memory' error?
Out of memory is exactly what it sounds like: your program is trying to hold more data on system memory than is available. The c...

más de 1 año hace | 1

| aceptada

Respondida
I need help with creating bounded logarithmic plot
Assuming you meant to have , then t = linspace(0,2*pi); x = exp(-t); % if constant, then x(1:numel(t))=exp(-1); y = t; plo...

más de 1 año hace | 0

Respondida
How to find the zero crossing in x and time data sets?
idx = find( f(2:end).*f(1:end-1)<0 ) Will return the left-hand indicies of cross-over points. To get the exact X-values where ...

más de 1 año hace | 0

Respondida
how to form a two-column array for a given but dimmension-unknown array?
You can make a row vector of any N dimensional matrix by linearizing, for example A( 1:numel(A), 1 ) = A(:); .Thus, you can a...

más de 1 año hace | 0

Respondida
Conditional Scatter plotting based on third data set
Assuming columns with 1's will only have 1's, and columns with 2's and 3's will never have 1's, then it is as simple as taking t...

más de 1 año hace | 0

| aceptada

Respondida
How to take 1 row on table 1 and compute it against every row of table 2 and do this for each row in table 1
Assuming the data is read into two variables, d1(1:N1,1:3) and d2(1:N2,1:3) by d1 = xlsread('Matlab Help.xlsx','Random','B2:D31...

más de 1 año hace | 0

| aceptada

Respondida
Using trapz just for positive areas
You need to use more fine-grid X data in polyval to get test points at y=0. xA_fine = linspace(xA(1),xA(end),100); fA_fine = ...

más de 1 año hace | 1

Respondida
Continue after .exe finishes
You can use system() function to pass the command (as a string) without the "!" symbol. If using unix OS, you can pipe (with the...

más de 1 año hace | 0

| aceptada

Respondida
stacked plot x axis change in 2015 matlab version
bar(Y(:,1),Y(:,2:end))

más de 1 año hace | 0

| aceptada

Respondida
Find the input values of a function within an output range.
If you cannot solve algebraically (no closed form solution), then fzero is the best bet. Something like this: % example y range...

más de 1 año hace | 1

| aceptada

Respondida
how to fix this error 'Index in position 2 exceeds array bounds.'?
The proximate reason for the error is that "Popbest" is empty, and so acessing the first column by Popbest(:,1) throws an error....

más de 1 año hace | 0

| aceptada

Respondida
How to show two axis on a plot only where i want them
You can get the handles for the left and right axes with yyaxis. yyaxis left; % Sets the current y-axis left left_ax = gca; ...

más de 1 año hace | 0

| aceptada

Respondida
How can I plot the maximum values of the double matrix ?
Max() has an optional third argument that determines the index along which to take the maximum. So for a 10x20 matrix A, A_max...

más de 1 año hace | 1

| aceptada

Respondida
Heat diffusion problem. Why my program is showing error when I am trying to change 'nx' value i.e. no of rows beyond 13 ? Is there any problem with time or timesteps??
It looks like you are not including the dt value in your stencil. You also need to be mindful of stability when setting the time...

más de 1 año hace | 1

| aceptada

Enviada


mat-op-ex
Matrix Operator Extraction Toolkit - Tools to obtain the matrix form of common MATLAB linear operations (e.g. trapz, interp) for...

alrededor de 2 años hace | 1 descarga |

Thumbnail