# the cyclist

### Alden Scientific

Head of Modeling and Statistics at Alden Scientific. 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.)

**Programming Languages:**

Python, R, MATLAB, SQL

**Spoken Languages:**

English

**Pronouns:**

He/him

**Feeds**

How can I replace the upper off diagonal(super diagonal) and lower off diagonal(sub diagonal) of a matrix?

% Arbitrary size N=5; % Example input A = rand(N); % NxN random matrix disp(A) % Vector to set as the sub- or superdiag...

2 days 前 | 1

How to Filter Rows of Cell Array By Date Range

Here is one way: %Date Range MinDate = datetime('14-Jul-2024'); MaxDate = datetime('17-July-2024'); %Cell Array a = cell(...

16 days 前 | 0

Can't click "Roll The Dice!" problem in intro to matlab cody problems therefor cannot earn badge.

I can't say for sure, but I expect that that problem was deleted from Cody (perhaps by the author). Consider contacting support...

27 days 前 | 0

Adjusting Y-Values in Histograms

Your question is not perfectly clear to me. If you don't want the values binned, I think you more likely want to use the bar fun...

1 month 前 | 0

fitlme different to lmer in R

Disclaimer: I don't fully understand the specifics on why you are seeing what you are. Thinking about my comment about being st...

2 months 前 | 1

ylabel changes position with ax.YAxisLocation = 'origin'

It's a bit kludgy, but rng default hold on scatter(-rand(1,10),rand(1,10),120,'or','filled') scatter(rand(1,10),rand(1,10),1...

2 months 前 | 1

How to determine feature importance using gradient boosting?

The model that is output from fitrensemble has a predictorImportance method for global predictor importance. You can also use s...

2 months 前 | 0

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What happens if I use fitcecoc for a two-class classification, and how is it different from fitcsvm in such a scenario?

Disclaimer: I have not directly tested this idea. The defalt binary learner for fitcecoc is SVM. Therefore, I would expect the ...

2 months 前 | 0

Accessing Fit Coefficients from Curve Fitting

data_fit is a cfit object. You can apply post-processsing steps to this object, as described in this documentation. It sounds l...

2 months 前 | 0

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"Try the New Desktop" icon persists even after uninstalling the add-on (New Desktop for MATLAB (Beta))

That icon is not related to your use of the beta release from the FEX. The New Desktop is always an option now (presumably until...

2 months 前 | 1

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"Arrays have incompatible sizes for this operation" error

It's difficult to know for sure, but I'm guessing those are the variables as they exist in the workspace, outside the function. ...

2 months 前 | 0

I run the code below and expect to get a uniform histogram. It's not. I don't understand why not.

It's because of your choice of 100 bins is tuned to the periodicity of your function in a way that makes it the counts chaotic n...

3 months 前 | 2

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Why I am not getting the same result for an integral of a piecewise function?

You have two mistakes in this code. First, you got the signs wrong on the check. It should be check1 = aux1 - (aux2 + aux3) Se...

3 months 前 | 1

How to save entire MATLAB workspace as a JSON file?

There is no built-in way to do this in MATLAB, and it strikes me as quite difficult to do in a way that is general enough to man...

3 months 前 | 1

Prevent Windows Update from shutting down Matlab session

When you say "stop my simulations from shutting down", do you mean "Have MATLAB pause the Windows update?" As a Mac user, I don...

3 months 前 | 0

how aggregate duraration and sum it in timetable

Here is one way: load("matlab_tt2") TT2.timeOfDay = timeofday(TT2.datt); equalDurationSum = groupsummary(TT2,"timeOfDay",...

3 months 前 | 0

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how to remove variables of a table with a zeros in it

% Example data x = ["a";"b";"c"]; y = [4;5;6]; z = [0;7;8]; tbl = table(x,y,z); % Find variables with a zero hasZero = a...

3 months 前 | 0

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Plotting error bars on grouped bar

You need the XEndPonits property of the bars. % Sample data data = [1.5, 2.3, 3.2; 2.0, 2.8, 3.5; 1.8, 2.5, 3.0]; errors = [0...

3 months 前 | 1

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fitPosterior warning: Why does fitPosterior output a warning when the transformation is a step function?

I would say that a warning could be warranted because perfect separability could be an indication of over-fitting, and that the ...

3 months 前 | 0

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i need to plus all numbers in my Array of 3x3 then divide that number by its area using save ,for loop, function

You can sum all the elements of an array using the sum function. For example A = magic(3) S = sum(A,"all") You can save to fi...

3 months 前 | 0

How can I make x and y axis dates with contour?

That limitation is a shame. One awkward solution is to convert the datetime values to datenums (which are purely numeric), and ...

3 months 前 | 0

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using PCA to filter outliers in MATLAB

There is a built-in MATLAB function, rmoutliers, for detecting and removing outliers. I frankly did not read all your code, but...

3 months 前 | 1

Detection of storms from precipitation data

I think this does what you want. It is easy to make minor indexing mistakes, so you should double-check: % Load data load("VE_...

3 months 前 | 0

How to calculate Bootstrap confidence interval

As you may have noticed already, the data have a huge variance around that fit: x = [6 10 14 20 26 34 38]'; y = [122 107 119 1...

3 months 前 | 0

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don't understand output of fitlme, intercept substituted for first line.

The output is not substituting 'Intercept' for a level of your coefficient. It looks like your variable voc_registers is catego...

3 months 前 | 0

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Does the curvefit toolbox return the equation for the best fit line (or curve)?

Yes, you can get the coefficients of the best-fit equation. @Torsten's comment illustrates where you can see them in the UI, and...

3 months 前 | 0

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what is the best way to learn deep learning for medical imaging?

If you are talking specifically about using MATLAB, then I suggest you start with the Deep Learning Tutorials and Examples with ...

3 months 前 | 0

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anyone can help me explain the meaning of the following code?

I ran your code here. It seems pretty obvious what it does, right? You might want to do the free online MATLAB Onramp tutorial,...

3 months 前 | 0

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Set scale of boxplots

% Make some pretend data rng default x = 1.e-5*rand(1000,16); % Boxplot boxplot(x) % Fix the y-axis scale ylim([0 1.e-...

3 months 前 | 0

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matrix, where each element is a column vector

ETATT=cell(11,7); % initial matrix Etat=zeros(1001,1); % column vector, contained in each element of the ETATT matrix % Fill...

3 months 前 | 0