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# the cyclist

##### Last seen: Today
4.077 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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Change color of graph at a certain value (temperature vs. time)
One option would be to draw the data as points, perhaps with a thin black line to guide the eye to time-consecutive points. rng...

4 dagen ago | 0

What is the best practice of conditional statements in solving a complicatedly branched system?
An alternative would be to build up your expression via logical components of this form a = 2.0676; b = -0.2309; c = 4.342 ...

4 dagen ago | 1

How to use diag() once and change values after certain element?
A simple way to construct the exact matrix in your first part is matrix = 2*eye(4) + diag([-1 -1 -1],-1) + diag([1 1 1],1) How...

4 dagen ago | 0

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Behaviour of backslash operator for non-square matrices least-squares fitting
They are equal, to within floating-point precision. Notice that max(abs(c1(:)-c2(:))) is around 1e-16.

4 dagen ago | 1

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How to save each term from a sum
clear n = input('Number of terms: '); terms = zeros(n,1); for ni = 1:n terms(ni)=terms(ni) + (sum(1/(ni^2)...

4 dagen ago | 0

keep getting errors on matlab
Instead of writing sin(t)cos(t) you need to put the explicit operations in, like this sin(t)*cos(t)

5 dagen ago | 0

Showing : At least one END is missing: the statement may begin here.
The last line of rng.m is endfunction but it should be just end I also spotted another problem, which is that you should hav...

6 dagen ago | 0

Reshaping a 2 d matrix into a 3 d matrix row wise.
For your small example, if A is your original matrix, then permute(reshape(A',3,2,[]),[2 1 3]) For the larger one, permute(re...

7 dagen ago | 0

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Fit multiple data with one mathmatical model/function
I would restructure my data (see attached), and use the nlinfit function from the Machine Learning and Statistics Toolbox. This...

7 dagen ago | 0

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Fill area between contour levels
I am hoping for your sake that there is a better way than this (possibly using the Image Processing Toolbox?), but here is one w...

7 dagen ago | 1

Turn a X Y Z matrix into a point cloud
xyzPoints = [1 8 9; 2 3 4; 9 8 6]; ptCloud = pointCloud(xyzPoints);

7 dagen ago | 0

Searching for minimum x root for known y
This code finds the minimum root, for y == 43. y = 43; p = [-0.1042 1.9167 13.062 39.333 45.083 21-y]; min(roots(...

8 dagen ago | 1

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get the x-value of a point on curve
When you say "get", do you mean from the vectors, or only from the curve? If you mean from the data, you can do, for example x...

8 dagen ago | 0

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How to Read and plot CSV file and delete infinity values from CSV file
I find that sometimes with these finicky imports it can be helpful to use the Import Data Tool. I used that as a basis to make ...

8 dagen ago | 0

Converting matirx into vektor inside a cell array
ev1 = cellfun(@(x)x(:,1),V,'UniformOutput',false); ev2 = cellfun(@(x)x(:,2),V,'UniformOutput',false);

8 dagen ago | 1

Filling areas between curves
If you put this line after your line plotting, you'll see the basics of using the patch command: patch([x1; x1(1)],[y1; y1(1)],...

9 dagen ago | 0

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How do you remove a trend from data without using the 'detrend' function?
Usually, when someone "doesn't want" to use a function, it means that it is homework, and they are not allowed to use a function...

9 dagen ago | 0

recursive function with 2 variables doesnt work
For me, your function works as expected. Maybe you accidentally also created a variable s in your workspace, and you are trying...

9 dagen ago | 0

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estimate main effects and interactions
I was able to replicate the effect estimates, but only via a rather odd normalization scheme of the variables: data = [1 10 220...

10 dagen ago | 0

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Receiving 'not enough input arguments' in code
You need rows>Rank instead of rows>rank MATLAB is case-sensitive. It would be better to have named that variable something t...

11 dagen ago | 0

How to get the indices of the values inside every bin i.e. histcounts2
Suppose you want to know which elements are in the bin that is 8 down and 6 across. Then binToFind = [8 6]; [tf,loc] = ismembe...

13 dagen ago | 1

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How to write a for loop that creates a vector of [1:1000, 1001:2000,....,n]
% Define block size and number of blocks blockSize = 1000; numberBlocks = 50; % Create vector of all values A = 1:(blockSi...

15 dagen ago | 0

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fitcecoc SVM with categorical predictors not predicting the correct label for multiclass problem.
I'm pretty sure you've got your dummy encoding wrong. You are treating 1,2 and 3 as if they are somehow the same categories in ...

15 dagen ago | 0

How can i include error calculation in the linear regression in a for loop?
The regress function outputs confidence intervals for the slope and intercept.

15 dagen ago | 0

Incorrect numerical integration, how to fix?
MATLAB's result is correct. You must have made a mistake on your calculator. You can verify this calculation that I entered int...

16 dagen ago | 0

How can I extract data and match it from two different data??
If your first vector is only ones and zeros, then it is as simple as idx = [ 0 0 0 0 1 1 1 0 0 0 ]; b = [ 5 5 5 5 10 10 10 6 6...

16 dagen ago | 0

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help with max function
This code will return the row and column indices where the entry is equal to the column's maximum. [rowIdx,colIdx] = find(A==ma...

18 dagen ago | 0

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Bar Plots with errorbars with limits
Do you mean something like this? % Pretend data x = linspace(0,10,25); y = linspace(0,1,25); se = y/10; % Amount that e...

18 dagen ago | 0

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Removing values from two different variables
% For each cell of AL, find the non-2's keepIndices = cellfun(@(x)x~=2,AL,'UniformOutput',false); % Keep the elements of AL ...

18 dagen ago | 0

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