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# the cyclist

##### Last seen: Today
4,315 total contributions since 2011

Data scientist at Cohen Veterans Bioscience; Obsessive runner. Professional Interests: Predictive modeling, statistics. (I don't respond to email via author page, but will usually look at a question if you send me a link to it.)

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draw a boxplot from a probability density function
Here is a very kludgy way to do it. You can generate a small "sample" dataset that has the same summary statistics as your PDF, ...

17 hours ago | 0

Delete overlaping intervals in matrix
I expect there is a more elegant approach, but here is a straightforward way: M = [100 200 5; 150 210 7; 205 300 9;...

4 days ago | 0

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Delete overlaping intervals in matrix
I believe this does what you want: M = [100 200; 150 210; 190 300; 300 400; 410 600; 500 700]; keepRow = M(2:end,1) >= M(1:end...

4 days ago | 1

I want to use the Python libraries in MATLAB
Have you seen this documentation on calling python modules from MATLAB?

4 days ago | 0

how can I put the histfit function in terms of probability?
Here's one way: % Made-up data data = randn(500,1); % Fit to a normal (or a different distribution if you choose) pd = fit...

6 days ago | 0

help with error "Reference to a cleared variable n"
Putting clear all inside the function clears the variable n that you just sent into it. You don't need that line.

6 days ago | 0

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Using regexp to extract day number from long string
Is the directory depth reliably constant? If so, then % Input data str = 'folder\files and things\1996\other folder\ 6 <month>...

7 days ago | 0

Limiting the values of a column
If you mean that y is a column vector, then y_new = y((y>=-10) & (y<=10)) will give you a new column vector with only the valu...

7 days ago | 0

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Need help fitting given data to an exponential function
If you have the Statistics and Machine Learning Toolbox, you might be able to use the expfit function. If not, and you don't ha...

9 days ago | 0

How to search for an exact string not just contains
Use strcmp instead, which checks for identical matches. loc = {'Las Vegas, NV','North Las Vegas, NV'}; match = strcmp(loc,'L...

9 days ago | 0

Counting every other number in a list
I'm not sure what you mean by "count" them, but the following vector will store every other element from mylist, starting with t...

10 days ago | 0

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gaussian plot on my histogram
If you have the Statistics and Machine Learning Toolbox, you can use the histfit function to do the histogram and gaussian fit a...

13 days ago | 0

Who is using the MATLAB Discord channel?
This is the first I've heard of MATLAB having a Discord channel

13 days ago | 1

Get size of each element in a cell
You can use the cellfun command: cellfun(@size,myCell,'UniformOutput',false)

14 days ago | 1

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How to interpret PCA
@Jin Woo: If search this forum for cyclist and pca, you will find a few question/answers where I explain a lot about the interp...

14 days ago | 0

Numbering results from for loop with the iteration they come from
Don't use separate variable names. Use the cell array data type: K{i} = ( ( EALtheta(i,1) * EALtheta(i,2) ) / EALtheta(i,3) )*...

16 days ago | 0

Array indices must be positive integers or logical values.
It seems that you have tried to use this line of code: funcnew01=z^5+z^3-pi; to define a general function on z. Then you try t...

16 days ago | 1

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Compute the summation of all elements square of matrix
This looks like homework. In the future, please listen to James Tursa's advice, and post what you have tried, be specific about...

17 days ago | 0

Why is the (second) if statement in the for loop not working?
I don't know if this is perfectly correct, but it is certainly closer: Where you have i_Last(i) = Faktor*(i_0+(i_Amp*(1-exp(-(...

21 days ago | 0

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How can I extract numbers from a column in a matrix dependent on a number in another column ?
If your matrix is A, then output = log(A(A(:,4)==2,9)); In case it is not obvious what that one line of code is going, work fr...

21 days ago | 1

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Different machine precision for scalars and vectors?
If you don't have a specific reason to be using a for loop here, why not also teach them canonical use of vectorized calculation...

22 days ago | 1

Combining your new code that aligns the values of t (but not using your attempt at creating the patch), and the same basic idea ...

22 days ago | 1

How can I create a scatterplot matrix?
Here is one way: T = readtable('Stress_Reactivity.xlsx'); figure gscatter(T.cort_3,T.diastolic_3,T.condition) I recommend ...

23 days ago | 0

Saving a m file
Are you using the MATLAB editor? On the editor tab, there is an icon for saving the file you are editing.

23 days ago | 0

Julian day to date
Here is one way: dateTable = readtable('KALAMARIA_2007.xlsx','Range','C:D'); julianDate = datetime(dateTable.YEAR,1,dateTabl...

23 days ago | 0

How to I find X unique combinations (order doesn't matter) of X numbers within an array of X numbers.
There's probably a more efficient way, since I effectively first find all combinations, but I think this does what you want, in ...

24 days ago | 1

unique vector with restrictions

24 days ago | 0

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Why do I get this error message "Array indices must be positive integers or logical values."
You have three distinct problems in this one line of code: Z = x.^2*y(y-1)*(y+1) One of them is causing the error you are seei...

25 days ago | 0

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