Rik

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2,478 total contributions since 2017

E-mails with feedback/questions about FEX submissions are welcomed. In general I will post e-mails about Answers on the related page, unless there is good cause not to do so.

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Answered
How to create a string that depends on user input variables?
You can create this text with sprintf and some minor tweaks: str=sprintf('p(%d)*x^%d +', [1:d;(d-1):-1:0]); str=strrep(str...

1 day ago | 0

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Adding numbers in a row vector
You can do it with a for loop, but you should use cumsum instead.

1 day ago | 0

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Answered
I keep getting the error "Dimension argument must be a positive integer scalar within indexing range"
The trapz function does not allow an anonymous function as second input. You will need to calculate the y values. f= @(x) 2...

1 day ago | 0

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Answered
I want to make a series using max & mins of this Integral and show that the series converges and has the limit pi/2.
Your code already is making a series. You could add the envelope, but the only thing you're missing in my opinion is adding the ...

3 days ago | 0

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Solved

Return a list sorted by number of consecutive occurrences
Inspired by Problem 38 by Cody Team. Given a vector x, return a vector y of the values in x sorted by the number of CONSECUTIVE...

4 days ago

Solved

Replicate elements in vectors
Replicate each element of a row vector (with NaN) a constant number of times. Examples n=2, A=[1 2 3] -> [1 1 2 2 3 3] ...

4 days ago

Solved

Get the elements of diagonal and antidiagonal for any m-by-n matrix
In the problem <http://www.mathworks.com/matlabcentral/cody/problems/858-permute-diagonal-and-antidiagonal Problem 858. Permute ...

4 days ago

Solved

Getting the indices from a matrice
Getting the indices from a matrice. Inspired by Problem 645. Getting the indices from a vector by the great Doug Hull. Given a...

4 days ago

Solved

Set the array elements whose value is 13 to 0
Input A either an array or a vector (which can be empty) Output B will be the same size as A . All elements of A equal to 13...

4 days ago

Solved

Construct an index vector from two input vectors in vectorized fashion
Create an index vector defined by two input vectors, one defining the beginnings of one or more index ranges, and the other defi...

4 days ago

Answered
create a new 4D Array from 2 others
I think I understand what you mean. The code below will overwrite all values that are not NaN for a given depth, which is equiva...

4 days ago | 0

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Answered
Generating a random number from array based on requirements
A=[1,2,3,4]; p=[10 20 30 40]; c=cumsum(p); isAllowed=[3,4]; while true [~,r]=histc(rand(1,1),[0 c/c(end)]); if ism...

5 days ago | 0

Answered
Graph window is blank
As most of the operation you perform don't work for most shapes of input data, I'm assuming you're calling this code with scalar...

5 days ago | 0

Answered
How to write this for loop as a while
Every for-loop can be re-written to a while-loop. y = 0; k = 1; while k<=999 y = y + k*k; k = k + 4; end

5 days ago | 1

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Modifying odd/even numbers of a column vector
If you have trouble with Matlab basics you may consider doing the Onramp tutorial (which is provided for free by Mathworks). x ...

5 days ago | 0

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Answered
Multi Dimension Matrix Elements multiplication
Not completely without loops, but this should be fast enough. You should also be aware that loops can sometimes be the fastest w...

5 days ago | 0

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How to run function between each row
pairs=nchoosek(1:size(data,1),2); for n=1:size(pairs,1) row_a=data(pairs(n,1),:); row_b=data(pairs(n,2),:); %cal...

5 days ago | 0

Answered
Single line plot with fixed axis
Every axes object has an XScale property you can set to 'log' to get the desired plot. You can use the normal plotting tools (e....

5 days ago | 1

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Answered
How to click points in a figure to generate a function/set of data?
I would suggest getpts, although there is an alternative that gives visual feedback: ginput.

5 days ago | 0

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how to generate 10^6 random binary values consisting only -1 and 1?
doc randi

5 days ago | 0

Answered
matrix step shift in each row
This method works without a loop. A =[ 1 2 3 4 5 ]; [X,Y]=ndgrid(1:numel(A)); X=X(end:-1:1,:); ind=mod(...

6 days ago | 0

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Answered
Nothing will be showing on plot
You are plotting single points, without changing the default (where points are not displayed, only the line connecting them). Yo...

6 days ago | 0

Answered
How can I calculate the revenue in a FOR loop?
Store the revenue in a vector you index with s. Then use sum to calculate the total.

9 days ago | 0

Submitted

GetWritableFolder
Return a folder with write permission.

9 days ago | 1 download |

Answered
Form a Matrix dependent of iterations
I'm going to assume your question is a homework assignment. That is why I will ignore the requirement of using a while loop, as ...

10 days ago | 0

Answered
how to save each array's results in dependent blank in GUI program base code?
For general advice and examples for how to create a GUI (and avoid using GUIDE), have look at this thread. Below I show you some...

10 days ago | 0

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Answered
How to detect certain pixel value in a stick.
Something like this will do it: A=imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/524729/image.png'); ...

10 days ago | 0

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Answered
Bar graph labels not aligning with index value
You need to set the location of the xticks as well, otherwise Matlab will use the current xticks and use your provided labels in...

10 days ago | 0

Answered
Get Data from a 16414x6 array to 365 arrays with size(48x3)
I would suggest using a 3D array instead. If you dynamically generate variable names you are shooting yourself in the foot. You ...

10 days ago | 1

Answered
zoom X axis only - app designer
Your app is a uifigure, so you can test this outside of AppDesigner. It turns out you need to be fairly specific with your handl...

10 days ago | 0