Stephen Cobeldick

Last seen: Today

7.139 total contributions since 2014

Suspensa Vix Via Fit

Stephen Cobeldick's Badges

Answered
How to find unique values in a matrix without looping over rows
M = randi([0,9],3,13) W = sort(M,2); W(diff(W,1,2)==0) = 0; W = sort(W,2) % optional

ongeveer 11 uur ago | 0

Answered
Build matrix of different size column vectors generated inside a for loop
Inside the loop store the vectors in a preallocated cell array. Then after the loop use PADCAT (download required): https://www...

ongeveer 15 uur ago | 0

Answered
How to extract numeric data between string lines?
str = fileread('02-2021-Clearance-Box005_fort72.txt'); rgx = '(?<=Number of hit cells:\s+\d+\s+)(\d+[^\n]*)'; tmp = regexp(str...

ongeveer 19 uur ago | 0

| accepted

Answered
Replacing a numberless string in matrix with a number
Where V is that column: V = ["female";"male";"female";"male";"male";"female"] X = strcmpi(V,"female")

ongeveer 21 uur ago | 1

Answered
how to extract an extra variable which is calculated in ode function to main workspace?
Ignore advice that you should use assignin or evalin, because this does not take into account how ODE solvers work, as well as b...

ongeveer 23 uur ago | 0

| accepted

Answered
Why does ishghandle(0) alwys return true?
Because the graphics root always exists: https://www.mathworks.com/help/matlab/creating_plots/graphics-objects.html Using zero...

2 dagen ago | 1

| accepted

Answered
pick elements from a 3d array, based on an indexing matrix
https://www.mathworks.com/help/matlab/ref/sub2ind.html % fake data: nr = 5; nc = 7; np = 3; A = randi(9,nr,nc,np); I = ran...

2 dagen ago | 0

| accepted

Answered
Loading data from structure, using variable
The most important step is to always load into an output variable (which itself is a scalar structure): S = load(...) % always ...

2 dagen ago | 2

| accepted

Answered
Sum per 2 elements in vector
A = [1;2;3;4;5;6]; B = A(1:2:end) + A(2:2:end) or more generally: B = sum(reshape(A,2,[]),1).' or B = reshape(A,2,[]).' * o...

3 dagen ago | 1

| accepted

Answered
Problem outerjoin two tables 20x1 ; 20x8
I don't see why outerjoin is required: newTable = [ArrayTime,ArrayZ]

3 dagen ago | 0

Answered
Matlab round the values and find function can not give the exact result(index)?!
"I used this expression format longE to consider the actual values" format longE does not show the "actual values", it just sho...

3 dagen ago | 0

| accepted

Answered
Import data from bpmn file into one string/char value Matlab
The simple solution: https://www.mathworks.com/help/matlab/ref/fileread.html str = fileread(...);

3 dagen ago | 0

| accepted

Answered
Getting extra parameters from ODE45 and the mystery transpose
Using the OutputFcn is a complex way to get the Fs values. The simpler approach is to run the ODE solver normally, and then run...

3 dagen ago | 0

Answered
Normalizing RGB coordinates in an image
You did not take into account the integer class that you are using. Most likely the image data is uint8, which supports values ...

3 dagen ago | 0

| accepted

Answered
dynamically save a matrix to a structure
Do NOT use eval for trivial code like this. That approach is slow, complex, inefficient, and not recommended. Rather than messi...

4 dagen ago | 0

Answered
Conditionally select from array of struct by membership of a list in struct element
X(1).Members = [1,2]; X(1).Name = 'Group 1'; X(2).Members = [2,3]; X(2).Name = 'Group 2'; F = @(n)arrayfun(@(s)any(s.Members...

6 dagen ago | 0

| accepted

Answered
Can I somehow improve performance of str2double?
The fastest conversion uses low-level commands, e.g. sprintf and sscanf. Instead of this: C = {'1.2','3.4','5.6'}; V = str2dou...

6 dagen ago | 1

| accepted

Answered
How to sort one array based on the order of a second array?
As far as I can tell, the order of Q is irrelevant. A = ["1a","1b","1c","1d","1e","2a","2b","2c","2d","2e"]; % sorted B = ["A1...

6 dagen ago | 1

| accepted

Answered
Reshape array such that boundaries remain the same
x = [0, 1, 2, 1, 0]; y = [0, 0.5, 1, 1.5, 2, 1.5, 1, 0.5, 0]; xnew = interp1(x,linspace(1,numel(x),numel(y)))

6 dagen ago | 0

| accepted

Answered
Why am I getting "Array indices must be positive integers or logical values" error?
Consider this indexing: x1(i-j+1) What value does it have on the last iteration of the j loop? (hint: zero). i-j+1 % that ind...

6 dagen ago | 1

| accepted

Answered
Get unknown variable from mat-file
Given only one variable saved in the mat file: tmpC = struct2cell(load(filename)); myVar = tmpC{1}; Do not worry about the t...

7 dagen ago | 0

| accepted

Answered
Extracting the numbers from file names and listing them in a column
C = {'Rpma26siatBz 9.500000 Bx 0.000000mT WWait 2.000000Sec.Bzat9.5mT83.png',... 'Rpma26siatBz 9.500000 Bx 100.000000mT WW...

7 dagen ago | 0

| accepted

Answered
sum contents of array in groups of 10
Where V is your 1x3001 vector: M = sum(reshape(V(1:3000),10,[]),1)

7 dagen ago | 0

| accepted

Answered
How to append for each iteration not using cells?
Replace yield(p) = [yield(p); {helper(k)}]; with yield = [yield; helper(:)];

7 dagen ago | 0

| accepted

Answered
How to solve preallocating speed of a variable?
One simple solution is given here: https://www.mathworks.com/help/matlab/matlab_oop/creating-object-arrays.html "To preallocat...

7 dagen ago | 1

| accepted

Answered
Undefined function 'split' for input arguments of type 'char'
The function split was introduced in R2016b, so you will not be able to use it with R2013a. You can probably replace that line ...

7 dagen ago | 0

Answered
Accessing data from a struct cell
Assuming that your structure is named S, you can loop over it like this: for k = 1:numel(S) plot(S(k).data) % default plot...

7 dagen ago | 0

Answered
Convert cell array to vector
S = load('timestamps.mat'); T = vertcat(S.ans{:}) M = seconds(mean(diff(duration(T,'InputFormat','hh:mm:ss.SSS'))))

8 dagen ago | 0

| accepted

Answered
Create a Slanted Linspace Matrix
hankel(1:4,4:7)

8 dagen ago | 0

| accepted

Answered
Maximum number of repeated values over an array
a = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,9]; x = cumsum([true;diff(...

8 dagen ago | 1

| accepted