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# the cyclist

##### Last seen: Today
4.195 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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combining matricies with common values
I'm not certain this is what you want, but this is my best guess: [tf,idx] = ismember(b(:,1),a(:,2)) complete = [a(idx,2) a(id...

4 Tage ago | 0

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how to calculate mean without considering the zero in matrix
Presumably the easiest way to do what you want is to use the nanmean function from the Statistics and Machine Learning Toolbox, ...

8 Tage ago | 0

Parsing a multi cell array into character vectors to place in table
Here is a method, using regexp to identify where the separators are, and then for loops to use the separators as the "fenceposts...

8 Tage ago | 0

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Distributing a cell array into another
Here is a straightforward way: A = {'Category1', 'Category2'}; B = {'Mon', 'Tues', 'Wed', 'Thurs' 'Fri', 'Sat', 'Sun'}; nA...

9 Tage ago | 0

Valid_date function
This syntax 1 <= day <= 30 does not check if day is between 1 and 30. You need to do that as two separate checks: (1 <= day) ...

9 Tage ago | 0

How do I create a matrix with all binary combinations?
There's an incredible obfuscated hack for this: N = 4; dec2bin(0:2^N-1)' - '0'

14 Tage ago | 1

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how to make a plot from my function results?
Here is an example using a for loop that calculates and plots the Gregory-Leibinz approximation to pi: n_max = 100; pi_appro...

14 Tage ago | 0

How do i type this long equation?
It is not possible to convert that expression to valid MATLAB syntax, because you have some mismatched parentheses. Unless I ma...

14 Tage ago | 0

Structures with multiple, conntected anonymous functions
Are you sure that y didn't exist in the workspace when you defined the structures? Because in a fresh workspace, S.x = 3 S.y =...

15 Tage ago | 0

How to reshape matrix in this way?
N = reshape(M.',2,6).'; You need to transpose first (and later back again), because the reshape command works down the columns....

15 Tage ago | 2

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Multiply values by the number of days in each month
C = rand(41,35,360) ; % random 3d data daysNonLeap = [31; 28; 31; 30; 31; 30; 31; 31; 30; 31; 30; 31]; daysLeap = daysNonLe...

16 Tage ago | 1

Adding elements to a 2D array
C = [A; B]

16 Tage ago | 0

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How do you use multiple indices to separate data and put in a structure?
I was pretty sure there was a simple vectorized way to do this, but it did not come to me right away. But then I remembered it: ...

16 Tage ago | 1

How do you use multiple indices to separate data and put in a structure?
Here's one straightforward way % Make up some data and indices A = rand(3672,10); B = 1:2:600; % Preallocate the cell arra...

16 Tage ago | 1

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Why Greek leters cannot be typed in legend?
What do you get if you do L = legend('EXP','CFD simulation r k-\epsilon','Inlet position','Location','Northeast'); L.Interpret...

24 Tage ago | 0

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fprintf to print to both file and command window
I doubt it. I'm not sure what your goal is, but it would certainly be trivial to write your own small function. Something like ...

28 Tage ago | 0

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Loops to create multiple graphs
The gross way, with dynamically named variables: CH01 = [3 5]; CH02 = [7 11]; for ii = 1:2 varString = sprintf('CH%02d...

28 Tage ago | 0

Unrecognized function in reinforcement learning toolbox
Do other functions from the toolbox work? Does the output of >> ver list the toolbox? If you go to the License Center, and s...

30 Tage ago | 0

How to write for loop to subtract the mean from each data point of the variables?
Why use a for loop? x - mean(x)

etwa ein Monat ago | 0

How do I calculate PMF with the random numbers I generated?
The PMF is the number of times each value was obtained, divided by the total number of rolls, right? I think you should be able...

etwa ein Monat ago | 1

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A/B testing
See this documentation page for the large number of hypothesis-testing functions available in the Statistics and Machine Learnin...

etwa ein Monat ago | 0

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Can i take correct date from this data?
You need to be precise with the format string. Try datetime(t,'InputFormat','MMM yyyy')

etwa ein Monat ago | 1

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How to populate array with column vectors of different lengths
I think this does what you want, in a slightly less complicated way: figure hold on for i = 1:size(ind_F,2) plot(ind_F(i...

etwa ein Monat ago | 0

Multi Variable Categorical Regression
The following code fits a binary regression tree to your data: baseballData = readtable('BaseballData.xlsx'); % Load the data i...

etwa ein Monat ago | 0

iteration on file name
Here is one way: for nf = 1:10 str1 = sprintf('%d',nf); str2 = sprintf('%d',mod(nf-1,5)+1); filename...

etwa ein Monat ago | 0

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How do i plot the line of best fit?
Use polyfit to find the line of best fit. Use the plot command to plot that line Use the hold command so that the new plot doe...

etwa ein Monat ago | 0

How to index a variable value and assign it to an array?
Do you mean simply y = d1 If not, can you give a more specific example of the input and output you would expect (not just a pr...

etwa ein Monat ago | 0

shuffling cards using only simple cuts
split = randi(numel(Deck)-1); Deck = [Deck(split+1:end),Deck(1:split)];

etwa ein Monat ago | 0

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Regression for non-parametric data
It is a common misconception that the data themselves have to be normally distributed, in order to satisify the assumptions of a...

etwa ein Monat ago | 0

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