# J. Alex Lee

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**Feeds**

Join tables based on times that are within 3 hours of each other

This may be one such "optimization", though i have no idea if it is faster, but it maybe is less "brute force"? A = table(["AAA...

8 months ago | 0

| accepted

A compact way to replace zeros with Inf in a matrix

You can implicitly index "linearly" for any arrays - it will do all the ind2sub and sub2ind in the background: % Input A = [0 ...

8 months ago | 2

| accepted

Question

Escape characters in compose with array input and minus sign *edit* with "empty" string ""

I have trouble understanding the conditions under which compose() works when passing combination of "empty" strings "", escape c...

9 months ago | 1 answer | 1

### 1

answerconvert patch structure to graph() object?

Found a more built-in way but you have to convert the structure to a triangulation % create structure by isosurface [x,y,z] = ...

9 months ago | 0

convert patch structure to graph() object?

Are you sure your method is giving you the graph you want? It looks like it counts edges twice, but not exactly. So my question...

9 months ago | 0

How to plot contour on a curved surface for the below problem?

This is how I would do it with the bump. % parameters z_root=0; z_top=150; Ri0 = 80; trunk.TRes = 360/5; trunk.ZRes = 3...

9 months ago | 1

plot every column in an excel sheet and the corresponding column in the second sheet in same box plot with header name as chart title.

T1 = readtable("example.xlsx","Sheet","TF off TS","NumHeaderLines",1); T2 = readtable("example.xlsx","Sheet","No twist free off...

1 year ago | 0

Markers on UIAxes in App Designer

you probably need to issue plot commands specifying "parent" as the app.UIAxes

1 year ago | 0

Solution of Fick's Second Law of Diffusion Equation

I agree with the general idea in Torsten's answer using FD and method of lines. Specifically what ode solver to use on the discr...

1 year ago | 2

Detect when UIfigure is open

the best i have been able to do is to not use appdesigner itself to create ui components and start the app very bare bones so th...

1 year ago | 0

Plot Stiffness of Unidirectional Composite in Polar Coordinate System

theta and rho are respectively angle and radius...so for example t = linspace(0,2*pi,500)'; r = cos(t).^4 + .5; polarplot(t,r...

1 year ago | 0

| accepted

Slower program due to an additional figure window

I think your issue is that call to getframe() needs app.UIAxes to be supplied, that is, getframe(app.UIAxes) otherwise it wil...

1 year ago | 0

Filled contour with whiteout regions based on xyz data

If you can tolerate manually identifying white-out regions (just by a single set of coordinates somewhere in the region, such as...

1 year ago | 1

Curvature of a 2D image

The calculation of arc length and curvature using arc length parameterization and its derivatives, given "perfect coordinates", ...

1 year ago | 0

| accepted

How to group statistics by 2 variables for plotting?

are you looking for something like this? load("VolcRegion_clust.mat") T = cell2table(VolcType_clust,"VariableNames",["Region...

1 year ago | 1

| accepted

Increasing speed by fixing axis and grid outside of a loop

I think what Torsten is getting after is: do you intend to keep the history of all the previous pairs you plotted? But I'm goin...

1 year ago | 0

| accepted

morphing a surface over 3D data

It's hard to give specific ideas without knowing the shape, but... "The final goal is to obtain a triangulated surface that con...

1 year ago | 0

how to remove jumps?

Are you looking at the diff() of the signals? Maybe you can find the locations of the jumps as where the largest absolute value ...

1 year ago | 0

| accepted

How to draw a ball by plot3?

like this? but it doesn't use plot3 [x,y,z] = sphere(64); p = surf(x,y,z,"FaceColor","interp","EdgeColor","none"); p.CData = ...

1 year ago | 0

条件ごとに計算させるにはどうすればよいか

Gomen, kana tukaemasen. mask ni kanshiteha "logical indexing" wo search shitemitekudasai: link @(x)fun ni kanshiteha "anonymou...

1 year ago | 2

条件ごとに計算させるにはどうすればよいか

Do you know about the function "atan2", which might be helpful M1 = readmatrix("tmp.txt"); tc = 1/1000000; % no need to...

1 year ago | 2

| accepted

Using readtable (or similar) to import multiple ranges of data

it's hard to say without seeing the csv file, but it sounds like the data is not really tabular, and you may be better off using...

1 year ago | 0

I want to store tables in a for loop to excel

Assuming the columns in the table are always the same, and you generate multiple versions of a table in the loop, and want to sa...

1 year ago | 0

| accepted

How to combine group of plots into one with separate marker

Assuming that each figure only has 1 axes and you want the first axes to be the one you want to copy into fig(1) = open('f1.fig...

1 year ago | 0

enable/disable menu next to radiobuttons when those are selected/deselected

You are hiding how you created the radio buttons in the gui creation, but a big question is whether when you say "2 button group...

1 year ago | 0

| accepted

How to select rows in a table containing both string and numbers?

Look up how to index tables, and ismember. % your table name: modal_displacements % extract the columns of interest, if you ...

1 year ago | 1

| accepted

Solved

Is this triangle right-angled?

Given three positive numbers a, b, c, where c is the largest number, return *true* if the triangle with sides a, b and c is righ...

1 year ago

Solved

Find a Pythagorean triple

Given four different positive numbers, a, b, c and d, provided in increasing order: a < b < c < d, find if any three of them com...

1 year ago

Solved

Is this triangle right-angled?

Given any three positive numbers a, b, c, return true if the triangle with sides a, b and c is right-angled. Otherwise, return f...

1 year ago

Solved

Triangle sequence

A sequence of triangles is constructed in the following way: 1) the first triangle is Pythagoras' 3-4-5 triangle 2) the s...

1 year ago