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ncorr is not working on MATLAB 2023b new version, it gives me an error. Does somebody know why? Thanks
Julian
Julian
Last activity on 28 Mar 2024

I know the latest version of MATLAB R2023b has this feature already, put it should be added to R2023a as well because of its simplicity and convenience.
Basically, I want to make a bar graph that lets me name each column in a basic bar graph:
y=[100 99 100 200 200 300 500 800 1000];
x=["0-4" "5-17" "18-29" "30-39" "40-49" "50-64" "65-74" "75-84" "85+"];
bar(x,y)
However, in R2023a, this isn't a feature. I think it should be added because it helps to present data and ideas more clearly and professionally, which is the purpose of a graph to begin with.
Dear all,
In an excel file, we have temperature (te) and humidity (hu) data in two columns. The Gaussian kernel-density estimation and best-fit quadratic curve were plotted. However, we need to determine whether the relationship is statistically significant or not, as well as the coefficient of determination (R2). For calulation of the both of them, we used functions like:
1. cofficient of determination aa= fitlm(te, hu)
2. statistically significant p= coefTest(aa)
Is it correct? If not, please provide the any other suggestions.
Thank you.
For example, my main line chart have values: X=[10 20 30 40 50] Y=[0.5 1.5 5 -6 4]. I need to add second X axis, with value [1 2 3 4 5] but but I would like the distance between individual points to be variable. For example, between points 1-2 d=25, between 2-3 d=10. I would like to define this distance freely.
Recently, I came across a post about the JIT compiler on this Korean blog. In the post. The writer discussed the concept of the "Compile Threshold" and how it is calculated.
"The JVM accumulates the number of calls for each method called and compiles when the number exceeds a certain number. In other words, there is a standard for checking how often it is called and then deciding, 'It is time to compile.' This standard is called the compilation threshold. But what is this and why should it be used as a standard?"
The concept of the "Compile Threshold," as used above, seems to be more commonly associated with Tracing just-in-time compilation.
The writer used the simple Java code below to calculate the threshold.
for (int i = 0; i < 500; ++i) {
long startTime = System.nanoTime();
for (int j = 0; j < 1000; ++j) {
new Object();
}
long endTime = System.nanoTime();
System.out.printf("%d\t%d\n", i, endTime - startTime);
}
Since the MATLAB execution engine uses JIT compilation, I just wanted to perform the same experiment that the writer did.
I experimented using simple codes based on the code in the blog. I iterated a function 500 time using for-loop and calculated the execution time for each iteration using tic and toc. Then I plotted the execution time for each loop as blow. First five execution times are much higher than followings (10 times!) The test is very rough so I am not sure that I can conclude "MATLAB has Compile Threshold and it is 5!" but this value is actually correct ;-)
t0 = 0;
tfinal = 10;
y0 = [20;20];
timeToRun = zeros(500,1);
for i = 1:500
tStart = tic;
[preypeaks,predatorpeaks] = solvelotka(t0, tfinal, y0);
tEnd = toc(tStart);
timeToRun(i) = tEnd;
end
VS Code Extension for MATLAB was introduced back in April and has been downloaded 75K times since. Do people here use VS Code for writing MATLAB code?
Matt J
Matt J
Last activity on 1 Mar 2024

Would it be a good thing to have implicit expansion enabled for cat(), horzcat(), vertcat()? There are often situations where I would like to be able to do things like this:
x=[10;20;30;40];
y=[11;12;13;14];
z=cat(3, 0,1,2);
C=[x,y,z]
with the result,
C(:,:,1) =
10 11 0
20 12 0
30 13 0
40 14 0
C(:,:,2) =
10 11 1
20 12 1
30 13 1
40 14 1
C(:,:,3) =
10 11 2
20 12 2
30 13 2
40 14 2
Image Analyst
Image Analyst
Last activity on 10 Nov 2023

Wait for Walter, the rest of us are mere users.
Image Analyst
Image Analyst
Last activity on 27 Nov 2023

Image Analyst
Image Analyst
Last activity on 14 Nov 2023

Image Analyst
Image Analyst
Last activity on 25 Oct 2023

Embarassed by Walter Roberson