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.)
Python, R, MATLAB, SQL
Spoken Languages:
English
Pronouns:
He/him
Feeds
Why is pagemtimes slower than just coding up the matrix multiplication?Especially on GPU.
It seems to me that the two functions are not calculating the same thing, based on the size of their respective outputs: rng ...
21 days 前 | 1
SVM Fitcsvm() thresholds vs ROC curve thresholds
fitcsvm() fits the best possible SVM to the data. That function itself does not make the predictions. The resulting model objec...
28 days 前 | 0
a function slows down my profiler: I would like to speed it up
It won't be a big speedup, but I would expect idx=find(Ntradess(id:-1:1,x)<=a1,1,'first'); to be consistently faster than idx...
1 month 前 | 0
Two lines of plot title with number and date time
Since R2020b, there is a subtitle function. Here is how I would have written your code, incorporating that and some other change...
1 month 前 | 0
Can't open additional instance of MATLAB in release 2024b?
R2024b Update 1 fixed this (presumed) bug.
1 month 前 | 0
提问
Can't open additional instance of MATLAB in release 2024b?
I'm on a Mac (M1), running the latest OSX. I don't seem to be able to open an additional instance of MATLAB by right-clicking o...
1 month 前 | 3 个回答 | 0
3
个回答KS TEST fails at 0.05 but passes at 0.01
R = load('R.txt'); coeff = betafit(R); a_mle = coeff(1); b_mle = coeff(2); [~,x] = ecdf(R); pd_12 = betacdf(x,a_mle,b...
1 month 前 | 0
| 已接受
How to create a symmetric 2D distribution from a novel distribution
I agree with @John D'Errico that we need more description. Do you just mean that you want to replicate f across another dimensio...
1 month 前 | 0
Box-Whisker Plot with 5 and 95 percentiles and non-symmetric distributions.
It's a bit kludgy, but here is a way to do it by directly editing the XData and YData of the whiskers and their caps. % Set see...
3 months 前 | 0
How to properly read a csv saved cell array.
@Walter Roberson's answer is the canonical one, to be sure. A csv simply cannot store the cell array as you hoped (and naively c...
3 months 前 | 1
Can MATLAB files that were created in the trial version be used in the full version?
No, there should be nothing different about any MATLAB files created in the trial version. All the happens when a license expire...
3 months 前 | 1
| 已接受
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...
3 months 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(...
4 months 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...
4 months 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...
4 months 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...
5 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...
5 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...
5 months 前 | 0
| 已接受
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 ...
5 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...
6 months 前 | 0
| 已接受
"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...
6 months 前 | 2
| 已接受
"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. ...
6 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...
6 months 前 | 2
| 已接受
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...
6 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...
6 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...
6 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",...
6 months 前 | 0
| 已接受
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...
6 months 前 | 0
| 已接受
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...
6 months 前 | 1
| 已接受
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 ...
6 months 前 | 0
| 已接受