Answered

How can I multiply two big matrices, avoiding out of memory?

You can process by chunk of smaller (100 here); % Generate small test data m = 100; n = 100^2; C = rand(m^2,3); % your [alph...

How can I multiply two big matrices, avoiding out of memory?

You can process by chunk of smaller (100 here); % Generate small test data m = 100; n = 100^2; C = rand(m^2,3); % your [alph...

2 hours ago | 0

Answered

How to sort a matrix's columns by using indexes

Short answer data = data(:,indA); Long answer load lung.mat data=lung; b = data(:,end) == 1; data1 = data(b,:); data2 ...

How to sort a matrix's columns by using indexes

Short answer data = data(:,indA); Long answer load lung.mat data=lung; b = data(:,end) == 1; data1 = data(b,:); data2 ...

15 hours ago | 0

Answered

Switching an array of Vectors from Cartesian to Spherical Coordinates

OK since nobody care to give you the complete commands I'll [az,el,r] = cart2sph(V(1,:),V(2,:),V(3,:)); S = [az; el; r]; % <- ...

Switching an array of Vectors from Cartesian to Spherical Coordinates

OK since nobody care to give you the complete commands I'll [az,el,r] = cart2sph(V(1,:),V(2,:),V(3,:)); S = [az; el; r]; % <- ...

18 hours ago | 0

Answered

Minimum and maximum values of a field in a structure array

arrayfun(@(s) min(s.f1), s)

Minimum and maximum values of a field in a structure array

arrayfun(@(s) min(s.f1), s)

22 hours ago | 0

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Answered

Matlab Gui Column Calculation Problems adds 48

Convert your GUI Data input using str2double, str2num etc >> str2double('0')+1 ans = 1 >> '0'+1 ans = 4...

Matlab Gui Column Calculation Problems adds 48

Convert your GUI Data input using str2double, str2num etc >> str2double('0')+1 ans = 1 >> '0'+1 ans = 4...

1 day ago | 0

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Answered

Sorting specific values of one matrix into another

Why not use Connected graph component?

Sorting specific values of one matrix into another

Why not use Connected graph component?

2 days ago | 0

Answered

How to get the longest consecutive values in a column vector and the position at which it starts

A=[0 0 0 1 0 1 1 1 0 0 0 0 0 1 1 1 1 1 1 1 1 1]' i=reshape(find(diff([0;A;0])~=0),2,[]); [lgtmax,jmax]=max(diff(i)); istart...

How to get the longest consecutive values in a column vector and the position at which it starts

A=[0 0 0 1 0 1 1 1 0 0 0 0 0 1 1 1 1 1 1 1 1 1]' i=reshape(find(diff([0;A;0])~=0),2,[]); [lgtmax,jmax]=max(diff(i)); istart...

2 days ago | 1

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Answered

I want the code to randomize the rows and present each row for 10 times

The array B of the below has exactly 10 times each row of A in random order: m = size(A,1); B = A(mod(randperm(10*m),m)+1,:); ...

I want the code to randomize the rows and present each row for 10 times

The array B of the below has exactly 10 times each row of A in random order: m = size(A,1); B = A(mod(randperm(10*m),m)+1,:); ...

2 days ago | 0

Answered

Generate matrix that is a product of its indices

n = 5; i = (1:n)'; j = 1:n; M = i.*j - (i+j)

Generate matrix that is a product of its indices

n = 5; i = (1:n)'; j = 1:n; M = i.*j - (i+j)

3 days ago | 1

Answered

permutations of a matrix

x = (1:5)'; n = size(x,1); m = 5; % size of b s = 3; % target sum(A(:)) [i,k] = ind2sub([m,n],nchoosek(1:m*n,s)); j = re...

permutations of a matrix

x = (1:5)'; n = size(x,1); m = 5; % size of b s = 3; % target sum(A(:)) [i,k] = ind2sub([m,n],nchoosek(1:m*n,s)); j = re...

3 days ago | 1

Answered

how do I improve this code?

x = [2 5 6 7 8]; y = [1 3 4 8 9]; z = x.*y; z(10) = 0; c = cumsum(z);

how do I improve this code?

x = [2 5 6 7 8]; y = [1 3 4 8 9]; z = x.*y; z(10) = 0; c = cumsum(z);

3 days ago | 1

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Answered

How to close the boundary of a surface already generated by filling the holes

Add the salt to suit your need Aorg = xlsread('Y_slice.xlsx'); gapmax = 5; % adjust to your need [m,n] = size(Aorg); A...

How to close the boundary of a surface already generated by filling the holes

Add the salt to suit your need Aorg = xlsread('Y_slice.xlsx'); gapmax = 5; % adjust to your need [m,n] = size(Aorg); A...

3 days ago | 1

Answered

determine combination of elements in matrix

lgt = 4; % number of elements nz = 2; % number of 0s j = nchoosek(1:lgt,lgt-nz); i = repmat((1:size(j,1))',[1 size(j...

determine combination of elements in matrix

lgt = 4; % number of elements nz = 2; % number of 0s j = nchoosek(1:lgt,lgt-nz); i = repmat((1:size(j,1))',[1 size(j...

4 days ago | 0

Answered

Copy a figure to a subplot including all elements

close all fig1 = figure(1); ax = axes('parent',fig1); h=plot(ax,rand(1,10)); xlabel(ax,'x'); ylabel(ax,'y'); title(ax,'s...

Copy a figure to a subplot including all elements

close all fig1 = figure(1); ax = axes('parent',fig1); h=plot(ax,rand(1,10)); xlabel(ax,'x'); ylabel(ax,'y'); title(ax,'s...

4 days ago | 0

Answered

Plot of an ellipsoid

% If your principal axis are (3x1) P1, P2, P3 and half length are (scalars) h1, h2, h3 Q = [P1(:), P2(:), P3(:)]; Q = Q .* ([...

Plot of an ellipsoid

% If your principal axis are (3x1) P1, P2, P3 and half length are (scalars) h1, h2, h3 Q = [P1(:), P2(:), P3(:)]; Q = Q .* ([...

4 days ago | 0

Answered

Find the angle between two points in 3D plot.

if the 3D (x-y-z) coordinates of your two points are P1 and P2, both are (3 x 1) or (1 x 3) vectors angleradian = acos((P2(2)-P...

Find the angle between two points in 3D plot.

if the 3D (x-y-z) coordinates of your two points are P1 and P2, both are (3 x 1) or (1 x 3) vectors angleradian = acos((P2(2)-P...

4 days ago | 1

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Answered

How do you chop a number to a specified number of significant digits, not round

2 digits fix(x*100)/100

How do you chop a number to a specified number of significant digits, not round

2 digits fix(x*100)/100

4 days ago | 2

Answered

Using maximum of optimisation variable as an upper bound for another variable

Not sure what you mean by "boundary condition" (there is no such thing in all optimization frameworks as far as I know), but tak...

Using maximum of optimisation variable as an upper bound for another variable

Not sure what you mean by "boundary condition" (there is no such thing in all optimization frameworks as far as I know), but tak...

5 days ago | 0

Answered

Draw partial spheroid include a spheroid

The code bellow us this FEX to generate mesh points. % radius of the inner/outer spherical parts r1 = 1; r2 = 2; n = 20; %...

Draw partial spheroid include a spheroid

The code bellow us this FEX to generate mesh points. % radius of the inner/outer spherical parts r1 = 1; r2 = 2; n = 20; %...

5 days ago | 1

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Answered

How to trim segments to fit a square

% Generate some test data, put 100 instead of 20 if you like X1=rand(20,1)*40; X2=rand(20,1)*40; Y1=rand(20,1)*60-10; Y2=r...

How to trim segments to fit a square

% Generate some test data, put 100 instead of 20 if you like X1=rand(20,1)*40; X2=rand(20,1)*40; Y1=rand(20,1)*60-10; Y2=r...

5 days ago | 1

Answered

Create volume out of two surfaces

Tetra mesh generation. Let you do exportation in STL file % Points in xy-plane nx = 100; px = linspace(1,50,nx); pyi = 5+s...

Create volume out of two surfaces

Tetra mesh generation. Let you do exportation in STL file % Points in xy-plane nx = 100; px = linspace(1,50,nx); pyi = 5+s...

5 days ago | 0

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Answered

pairs of consecutive numbers

A=[5 3 4 1]; As=sort(A); b=diff(As)==1; pairs=As(b)'+[0 1]; notpair = setdiff(A,p(:))

pairs of consecutive numbers

A=[5 3 4 1]; As=sort(A); b=diff(As)==1; pairs=As(b)'+[0 1]; notpair = setdiff(A,p(:))

5 days ago | 1

Answered

How can I rotate and reflect subplots as a group?

x = rand(5,9); y = rand(5,9); c = rand(5,9); close all % Normal figure for h=1:9 [m,n] = ind2sub([3 3],h); ...

How can I rotate and reflect subplots as a group?

x = rand(5,9); y = rand(5,9); c = rand(5,9); close all % Normal figure for h=1:9 [m,n] = ind2sub([3 3],h); ...

5 days ago | 0

Answered

how to add all 2d matrices in a 4D matrix???

sum(sum(A,3),4) or sum(A(:,:,:),3)

how to add all 2d matrices in a 4D matrix???

sum(sum(A,3),4) or sum(A(:,:,:),3)

5 days ago | 0

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Answered

Calculation of unknown values of two equations without Symbolic Math toolbox

C = [1 1; -3 -2] \ [29; -70]

Calculation of unknown values of two equations without Symbolic Math toolbox

C = [1 1; -3 -2] \ [29; -70]

6 days ago | 0

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Answered

Multiplying 3D matrices

There is no stock function (what a MATRIX LABORATORY doesn't have such feature?), but here it is MTIMESX

Multiplying 3D matrices

There is no stock function (what a MATRIX LABORATORY doesn't have such feature?), but here it is MTIMESX

6 days ago | 0

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Answered

How to round up components of a matrix to 1

>> A=[0.818655843258541 0.381356605388963 0.286089112378312 -0.0340005479718328 0.0773489731425248 -0.0465565535336793 -0.0390...

How to round up components of a matrix to 1

>> A=[0.818655843258541 0.381356605388963 0.286089112378312 -0.0340005479718328 0.0773489731425248 -0.0465565535336793 -0.0390...

6 days ago | 0

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Answered

random order of elements in array meeting some conditions

Dynamic programming rpermc() %% save the rest in rpermc.m if needed function r = rpermc() while true r = rpc([], 20:5...

random order of elements in array meeting some conditions

Dynamic programming rpermc() %% save the rest in rpermc.m if needed function r = rpermc() while true r = rpc([], 20:5...

6 days ago | 0

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