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Complex matrix multiplication with pagemtimes

This really has nothing to do with the maturity of MATLAB ... every language that uses BLAS routines in the background will have...

Complex matrix multiplication with pagemtimes

This really has nothing to do with the maturity of MATLAB ... every language that uses BLAS routines in the background will have...

5 Monate vor | 2

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Matrix power vs for loop

Note that the A^endtime method is probably going to be more accurate as endtime gets larger. The loop method can have a tendancy...

Matrix power vs for loop

Note that the A^endtime method is probably going to be more accurate as endtime gets larger. The loop method can have a tendancy...

6 Monate vor | 0

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error: matrix dimensions must agree

I would presume you may need element-wise operators. Try this: func = @(K_a,freq)(-K_a./(tan(2*pi*freq*h.*(1 + 0.19./((K_a/60 +...

error: matrix dimensions must agree

I would presume you may need element-wise operators. Try this: func = @(K_a,freq)(-K_a./(tan(2*pi*freq*h.*(1 + 0.19./((K_a/60 +...

6 Monate vor | 0

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Average every 3 rows of 1 column in a 12 x 8 array

E.g., Data = [ 34 6 4 -6.60874766440390 -40.7725049965035 16217 0.289000000000000 1.02200000000000 35 6 5 -6.54326464...

Average every 3 rows of 1 column in a 12 x 8 array

E.g., Data = [ 34 6 4 -6.60874766440390 -40.7725049965035 16217 0.289000000000000 1.02200000000000 35 6 5 -6.54326464...

6 Monate vor | 0

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Converting 2D cell array to 3D matrix

E.g., MyCell = repmat({(1:4)'},2,3) % small sample data [m,n] = size(MyCell); reshape(cell2mat(MyCell(:)').',m,n,[]) size(an...

Converting 2D cell array to 3D matrix

E.g., MyCell = repmat({(1:4)'},2,3) % small sample data [m,n] = size(MyCell); reshape(cell2mat(MyCell(:)').',m,n,[]) size(an...

6 Monate vor | 1

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How can I calculate the "Median" of floating point numbers

E.g., x = randi(10,2,3) y = randi(10,2,3) z = randi(10,2,3) xyz = cat(3,x,y,z) result = median(xyz,3)

How can I calculate the "Median" of floating point numbers

E.g., x = randi(10,2,3) y = randi(10,2,3) z = randi(10,2,3) xyz = cat(3,x,y,z) result = median(xyz,3)

6 Monate vor | 0

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transposing 3d matrix with permute function

MATLAB does not store trailing singleton (1) dimensions beyond the 2nd dimension. Once you permute that 1 into the 3rd dimension...

transposing 3d matrix with permute function

MATLAB does not store trailing singleton (1) dimensions beyond the 2nd dimension. Once you permute that 1 into the 3rd dimension...

6 Monate vor | 2

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Scalar structure required for this assignment.

This? [Sis.On] = D_{:,2};

Scalar structure required for this assignment.

This? [Sis.On] = D_{:,2};

6 Monate vor | 0

Frage

LU decomposition algorithm change

For this particular example: A=[ 1 2 3; 4 5 6; 7 8 9; 10 11 12]; I get two different results depending on...

6 Monate vor | 2 Antworten | 0

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Inserting a double to a cell

E.g., x = randi(100,10,10) % sample data columns = [4,7]; % columns to check minx = min(x(:,columns)) % minimum of the two co...

Inserting a double to a cell

E.g., x = randi(100,10,10) % sample data columns = [4,7]; % columns to check minx = min(x(:,columns)) % minimum of the two co...

6 Monate vor | 0

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Using Matlab to solve 1D Schrödinger Equation (Strange Eigenfunctions)

Python: return is misspelled retrun The mL2V( ) function returns 1000*(y-1/2)**2 I don't see where y is defined prior to the ...

Using Matlab to solve 1D Schrödinger Equation (Strange Eigenfunctions)

Python: return is misspelled retrun The mL2V( ) function returns 1000*(y-1/2)**2 I don't see where y is defined prior to the ...

6 Monate vor | 0

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1×0 empty double row vector using find

Welcome to the world of floating point arithmetic. For your specific example, they are not equal. E.g., x=[0 0.1 0.2 0.3 0.4 0....

1×0 empty double row vector using find

Welcome to the world of floating point arithmetic. For your specific example, they are not equal. E.g., x=[0 0.1 0.2 0.3 0.4 0....

6 Monate vor | 1

Beantwortet

How to plot the first derivative of solution?

After the ode45( ) call, simply pass your x solution through your derivative function to obtain the xdot values. You can either ...

How to plot the first derivative of solution?

After the ode45( ) call, simply pass your x solution through your derivative function to obtain the xdot values. You can either ...

6 Monate vor | 0

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optimizing: fastest way to detect if ANY points are within distance N of points?

Here is a naive brute force mex routine you can try out. It makes no attempts at cache optimization or multi-threading, and is p...

optimizing: fastest way to detect if ANY points are within distance N of points?

Here is a naive brute force mex routine you can try out. It makes no attempts at cache optimization or multi-threading, and is p...

7 Monate vor | 0

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"roots" call is not providing the correct answer

Rename your old roots file (preferred method) or move it to a directory that is not on the MATLAB path. That way it won't shadow...

"roots" call is not providing the correct answer

Rename your old roots file (preferred method) or move it to a directory that is not on the MATLAB path. That way it won't shadow...

7 Monate vor | 1

Beantwortet

How can ı solve this error ??Unable to perform assignment because the size of the left side is 1-by-5 and the size of the right side is 26-by-1.

You could expand the size of the LHS array. E.g., poles_real(i, 1:numel(roots_poly)) = real(roots_poly); poles_imag(i,...

How can ı solve this error ??Unable to perform assignment because the size of the left side is 1-by-5 and the size of the right side is 26-by-1.

You could expand the size of the LHS array. E.g., poles_real(i, 1:numel(roots_poly)) = real(roots_poly); poles_imag(i,...

7 Monate vor | 0

Beantwortet

angle of a vector centered at a certain point

Once you have the vectors, you can calculate the angles between the vectors using the technique I posted here: https://www.math...

angle of a vector centered at a certain point

Once you have the vectors, you can calculate the angles between the vectors using the technique I posted here: https://www.math...

7 Monate vor | 0

Beantwortet

How to expand dimension of a 2D array

All MATLAB trailing singleton (1) dimensions beyond the 2nd dimension are not physically stored, and will not show up in a size(...

How to expand dimension of a 2D array

All MATLAB trailing singleton (1) dimensions beyond the 2nd dimension are not physically stored, and will not show up in a size(...

7 Monate vor | 2

Beantwortet

A single precision matrix multiplication problem

Somewhat related side comments: In general, the BLAS/LAPACK libraries do not contain mixed type argument routines. E.g., there ...

A single precision matrix multiplication problem

Somewhat related side comments: In general, the BLAS/LAPACK libraries do not contain mixed type argument routines. E.g., there ...

7 Monate vor | 2

Beantwortet

How is this even logical?

When assigning into rows or columns via indexing, MATLAB will conform a RHS vector from row or column to row or column if necess...

How is this even logical?

When assigning into rows or columns via indexing, MATLAB will conform a RHS vector from row or column to row or column if necess...

7 Monate vor | 0

Beantwortet

Matlab crashes when running a specific Fortan MEX file under MacOS

The MATLAB Fortran API interface needs to be treated as a pass-by-reference interface. That means you need to have the exact typ...

Matlab crashes when running a specific Fortan MEX file under MacOS

The MATLAB Fortran API interface needs to be treated as a pass-by-reference interface. That means you need to have the exact typ...

7 Monate vor | 0

Beantwortet

What does [n==0] means?

Try it out and see: n = 3; N = 3; n == 0 n == N n = randi(4,1,10) - 1 n == 0 n == N Returns logical true/false where val...

What does [n==0] means?

Try it out and see: n = 3; N = 3; n == 0 n == N n = randi(4,1,10) - 1 n == 0 n == N Returns logical true/false where val...

7 Monate vor | 0

Beantwortet

How to update a symmetric matrix?

E.g., M = rand(6)<0.3; M = double(logical(M+M')) % an arbitrary symmetric matrix VarMin= 1; % Lower Bound of Variables...

How to update a symmetric matrix?

E.g., M = rand(6)<0.3; M = double(logical(M+M')) % an arbitrary symmetric matrix VarMin= 1; % Lower Bound of Variables...

7 Monate vor | 0

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Recursive Method returning answers backwards

This is a very convoluted way to program the Euler method. There is no need for recursion here, just use simple loops instead. ...

Recursive Method returning answers backwards

This is a very convoluted way to program the Euler method. There is no need for recursion here, just use simple loops instead. ...

7 Monate vor | 1

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How to randomize order of functions

E.g., Using the cell array approach with randperm: function [results] = runTests(testparameters) f = {@test1,@test2,@test3,@te...

How to randomize order of functions

E.g., Using the cell array approach with randperm: function [results] = runTests(testparameters) f = {@test1,@test2,@test3,@te...

8 Monate vor | 0

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eval() is too slow to numerically evaluate a function with X(t) and Y(t).

Something like this? syms X(t) Y(t) Vfun = [2*X + Y ; cos(X)*X^2 + Y^3 ; 3 + sin(Y)] syms x y vfun = subs(Vfun,[X Y],[x y])...

eval() is too slow to numerically evaluate a function with X(t) and Y(t).

Something like this? syms X(t) Y(t) Vfun = [2*X + Y ; cos(X)*X^2 + Y^3 ; 3 + sin(Y)] syms x y vfun = subs(Vfun,[X Y],[x y])...

8 Monate vor | 0

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I have one column data 57600 points, how can i convert it to 240 by 240 matrix!

x = your column vector result = reshape(x,240,240); or you might need the transpose: result = reshape(x,240,240).';

I have one column data 57600 points, how can i convert it to 240 by 240 matrix!

x = your column vector result = reshape(x,240,240); or you might need the transpose: result = reshape(x,240,240).';

8 Monate vor | 0

Beantwortet

I want to calculate pi^2 to 22 decimal places

You can use this excellent FEX submission by John D'Errico: https://www.mathworks.com/matlabcentral/fileexchange/36534-hpf-a-bi...

I want to calculate pi^2 to 22 decimal places

You can use this excellent FEX submission by John D'Errico: https://www.mathworks.com/matlabcentral/fileexchange/36534-hpf-a-bi...

8 Monate vor | 2

Beantwortet

How to stop running code once conditions are met?

If your Birthday function is supposed to represent only one trial (a reasonable thing to do), then you should be returning n, no...

How to stop running code once conditions are met?

If your Birthday function is supposed to represent only one trial (a reasonable thing to do), then you should be returning n, no...

8 Monate vor | 0

Beantwortet

How to fix the must be a column vector error?

You should double check your derivative function. Shouldn't the result be a 4-element column vector that is a function of q? Ne...

How to fix the must be a column vector error?

You should double check your derivative function. Shouldn't the result be a 4-element column vector that is a function of q? Ne...

8 Monate vor | 0