Read row x to row y in a textfile
Is the following working? [T1,PSA1]=textread('FFC_M7_1.txt', '%f %f %*s %*s','headerlines',32781); or content = f...

2 years ago | 1

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How do i count a certain class of numbers in a 100x100 matrix?
>> sum(~imag(za(:))) ans = 8627

2 years ago | 0

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When was 'tokenize' dropped from regexprep?
R14 You'll have to write a book about regexp after all these threads ;-) *EDIT:* found it mentioned in the PDF release not...

2 years ago | 1

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Solved

Check if number exists in vector
Return 1 if number _a_ exists in vector _b_ otherwise return 0. a = 3; b = [1,2,4]; Returns 0. a = 3; b = [1,...

2 years ago

Text Extraction and retrieval
Here is another approach based on pattern matching: >> data = regexp(fileread('data.txt'), '(?<=<P[^>]+>\s*)[\w ]+', 'match'...

2 years ago | 2

Find cell containing part of a string
If you cannot assume that keywords are separated by white spaces: >> find(cellfun(@(x)~isempty(strfind(stringToCheck,x)), co...

2 years ago | 0

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Square matrix with relationships among equal rows.
B = all(permute(A, [1,3,2]) == permute(A, [3,1,2]), 3) ; and if you have a version of MATLAB < R2016b: B = all(bsxfun(...

2 years ago | 1

MATLAB Answers Wish-list #4 (and bug reports)
Rep. points should be convertible to bitcoin!

2 years ago | 1

Sparse indexing expression is likely to be slow
When building sparse matrices using an iterative approach, it is often more efficient to build vectors of indices and values ite...

2 years ago | 0

Create a method that overloads a property?
We usually do this using setters and getters. You will find plenty of doc if you google these terms, e.g. <https://www.mathworks...

2 years ago | 1

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Here is one way: data = textscan( fileread( 'data.txt' ), '%s' ) ; data = reshape( str2double( data{1} ), 17, [] ).' ; d...

2 years ago | 0

Speed processing if algorithm is partitioned in well-organized minor functions
Part of programming consists in understanding where and how code can be segmented into simple self-consistent functional blocks....

2 years ago | 0

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Comparing elements in each row of a matrix
Here is one way to do it without any loop (with MATLAB R2016b or more recent): >> AQ_z_matrix=[10000 11000 20000; 10000 1100...

2 years ago | 1

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Matrix Elements Re-ordering
>> B = reshape( A, 2, [] ).' B = 1 3 5 7 2 4 6 8

2 years ago | 1

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Please someone solve the error of unexpected error at x=D./2f
What is |2f|? Is this what you are trying to compute? x = D ./ (2*f) ;

2 years ago | 0

How to fill a 3D array with values calculated in a loop?
This would be one way to do it if you have MATLAB R2016b or newer: A = sum( D .* permute( d(1,:), [1, 3, 2] ), 3 ) ; % F...

2 years ago | 0

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Matlab and memory use
MATLAB default numeric type/class is "double" (for double-precision floating-point) stored on 8 bytes (= 64 bits). Your array wi...

2 years ago | 0

How to write a line of statement with two vector of different size using no loops
>> H2 = (n >= 0) .* sum(r.' .* p.'.^n) ; >> isequal( H2, H ) ans = logical 1 if it doesn't work, you may have a...

2 years ago | 0

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How can I add normal text as well as Latex symbols on a figure axis?
This is something that I don't fully understand actually, and I'd love to get some explanation from TMW. Some times (maybe on ol...

2 years ago | 1

Repeat row of a matrix
Here is one way to achieve it. If >> a = [1;2;3] ; >> B = randi( 10, 3, 2 ) B = 3 10 6 2 10 ...

2 years ago | 0

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How to sort a matrix based on one index I have ?
I guess/hope that you made a mistake when you built your example of sorted |t| (that seems to be sorted according to |c=[2;1;3]|...

2 years ago | 1

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Find index of first zero searching from left first column first row, then find index of first zero searching from last column last row
MATLAB stores data column first in memory. Accessing your 2D array linearly follows this structure. Evaluate >> M(:) and ...

2 years ago | 1

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using find function and comparing results
Don't save regular numeric data in cell arrays, you cannot compute with them and you have to go through notation- and computatio...

2 years ago | 0

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Matlab Performance Question (Nested for loops vs inbuilt functions (cellfun, circshift))
Well, I got a few minutes at the airport. Try this in your comparison: tic ; s = cellfun('length', t) ; v = cumsum(s)...

2 years ago | 1

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Why do I get "Index exceeds matrix dimensions"?
Numeric arrays cannot store arrays of two characters. Try with a cell array. Also, don't index arrays with characters but with n...

2 years ago | 0

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search for elements of a vector in a matrix (without using ismember)
*EDIT:* I took 3 more minutes and I profiled a small test case (N=1e7, n=1e2). *ISMEMBER is more efficient!* Here is an alter...

2 years ago | 3

How to overlay randomized point grid on photo?
I = imread( 'MyImage.png' ) ; x = rand( 1, 50 ) * size( I, 2 ) ; y = rand( 1, 50 ) * size( I, 1 ) ; imshow( I ) ; h...

2 years ago | 0

Deleting Nonzero elements in each row
Here is one way: >> A A = 0 0 5 5 4 1 0 1 3 0 4 2 0 0 3...

2 years ago | 0

How to group rows of data into a cell of a cell array?
Here is one way. We start by building a fake data set: >> A = [rand(10,3), randi(2,10,3)] A = 0.7513 0.8407 0.3...

2 years ago | 1

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