58 total contributions since 2017

Answered

How to sum n lines of a matrix to another matrix?

n=2; TotalApit = reshape(sum(reshape(Apit,[n 102/n 5 1000])),[102/n 5 1000]);

How to sum n lines of a matrix to another matrix?

n=2; TotalApit = reshape(sum(reshape(Apit,[n 102/n 5 1000])),[102/n 5 1000]);

1 year ago | 0

Answered

Determining the max angle from the cell array

This should do. Change |ncells| as desired. ncells = length(Ang_F1); max_edges_anglesR = max(angle(reshape(cell2mat(Ang...

Determining the max angle from the cell array

This should do. Change |ncells| as desired. ncells = length(Ang_F1); max_edges_anglesR = max(angle(reshape(cell2mat(Ang...

1 year ago | 0

| accepted

Answered

what is the MATLAB function to evaluate ncr value when n is real

If |n| and |r| are both non-negative integers, and |n >= r|, use: nCr = nchoosek(n,r) If n and/or r can be negative, yo...

what is the MATLAB function to evaluate ncr value when n is real

If |n| and |r| are both non-negative integers, and |n >= r|, use: nCr = nchoosek(n,r) If n and/or r can be negative, yo...

1 year ago | 0

| accepted

Answered

Multiplying two matrices of probabilities with different sizes.

I don't think there is anything wrong with your code. What is wrong is your interpretation of the outcome of multiplying your ma...

Multiplying two matrices of probabilities with different sizes.

I don't think there is anything wrong with your code. What is wrong is your interpretation of the outcome of multiplying your ma...

1 year ago | 0

Answered

Plot trajectory colorized according to the standard deviation

Plot your data as a |surface| with zero height. x = vector_of_latitudes; y = vector_of_longitudes; z = zeros(size(...

Plot trajectory colorized according to the standard deviation

Plot your data as a |surface| with zero height. x = vector_of_latitudes; y = vector_of_longitudes; z = zeros(size(...

1 year ago | 0

Answered

picking maximum difference across entries of row vectors, Part 3

A = [NaN NaN 3 9 4 ; 1 100 NaN 34 12]; maxdiffs = max(sort(A,2),[],2) - min(sort(A,2),[],2);

picking maximum difference across entries of row vectors, Part 3

A = [NaN NaN 3 9 4 ; 1 100 NaN 34 12]; maxdiffs = max(sort(A,2),[],2) - min(sort(A,2),[],2);

1 year ago | 0

| accepted

Answered

Extract structure array elements into seperate matrix

No, that syntax won't work. If you want a one-liner, here's one alternative: extracted = cellfun(@(x) x(1,2), {data.datablo...

Extract structure array elements into seperate matrix

No, that syntax won't work. If you want a one-liner, here's one alternative: extracted = cellfun(@(x) x(1,2), {data.datablo...

1 year ago | 0

| accepted

Answered

How can I find columns with all zeros in my matrix?

cols_with_all_zeros = find(all(A==0)); % all zeros cols_with_3_nonzeros = find(sum(A~=0)==3); % exactly 3 non-zeros

How can I find columns with all zeros in my matrix?

cols_with_all_zeros = find(all(A==0)); % all zeros cols_with_3_nonzeros = find(sum(A~=0)==3); % exactly 3 non-zeros

1 year ago | 2

| accepted

Answered

Finding the first element of a 1-D array that yields a negative result.

x = normrnd(0,1,[1,20]); % generate 20 random numbers y = x(find(x<0,1)); % assign the first negative random value to y

Finding the first element of a 1-D array that yields a negative result.

x = normrnd(0,1,[1,20]); % generate 20 random numbers y = x(find(x<0,1)); % assign the first negative random value to y

1 year ago | 0

Answered

How to multiply matrices using a for loop

p = rand(4,1); % 4x1 vector P = rand(4,4); % 4x4 matrix pstar = 10; while p(1)<pstar % stop multiplying if p(1) reach...

How to multiply matrices using a for loop

p = rand(4,1); % 4x1 vector P = rand(4,4); % 4x4 matrix pstar = 10; while p(1)<pstar % stop multiplying if p(1) reach...

2 years ago | 0

Answered

Find unique in matrix of x,y coordinates

Did you try this? [C,IA] = unique(A,'rows'); |C| contains all unique rows of |A|. |IA| contains the indices of the rows...

Find unique in matrix of x,y coordinates

Did you try this? [C,IA] = unique(A,'rows'); |C| contains all unique rows of |A|. |IA| contains the indices of the rows...

2 years ago | 0

Answered

How do I create a for loop for the this example?

You can use |eval|. Something like this should work, although you need to take care of saving your variables at the end of each ...

How do I create a for loop for the this example?

You can use |eval|. Something like this should work, although you need to take care of saving your variables at the end of each ...

2 years ago | 0

| accepted

Answered

How to sample Multinomial Distribution

It is difficult to read your question. Please use underscore to separate your variable names from subscripts. Here's a solution ...

How to sample Multinomial Distribution

It is difficult to read your question. Please use underscore to separate your variable names from subscripts. Here's a solution ...

2 years ago | 1

| accepted

Answered

How to plot 3d line on fit function?

You need to use |hold on|. For example, x = rand(100,1); y = rand(100,1); z = x.^2 + y; sf = fit([x, y],z,'poly...

How to plot 3d line on fit function?

You need to use |hold on|. For example, x = rand(100,1); y = rand(100,1); z = x.^2 + y; sf = fit([x, y],z,'poly...

2 years ago | 0

| accepted

Answered

Element by Element Subtraction

|minus| operator in Matlab can inherently handle this, so you don't need a loop. Checkout >> |help minus|. For your case, some...

Element by Element Subtraction

|minus| operator in Matlab can inherently handle this, so you don't need a loop. Checkout >> |help minus|. For your case, some...

2 years ago | 0

Answered

how to change Function value intiialization? mine is start with 0. i want start with -1

f = zeros(1,length(t)) - 1;

how to change Function value intiialization? mine is start with 0. i want start with -1

f = zeros(1,length(t)) - 1;

2 years ago | 0

Answered

How to make a break on x axis and have two sets of values?

You need to read this article on indexing: <https://www.mathworks.com/company/newsletters/articles/matrix-indexing-in-matlab.htm...

How to make a break on x axis and have two sets of values?

You need to read this article on indexing: <https://www.mathworks.com/company/newsletters/articles/matrix-indexing-in-matlab.htm...

2 years ago | 0

Answered

quadprog 'trust-region-reflective' algorithm error

As you said, _the only limit to the use of this algorithm is that only equality constraints or bound constraints can be used but...

quadprog 'trust-region-reflective' algorithm error

As you said, _the only limit to the use of this algorithm is that only equality constraints or bound constraints can be used but...

2 years ago | 1

Answered

Sorting from the maximum value to minimum value in a vector

A=[2 5 8 7 8 9 3 7 6 5 4 1]; Asorted = sort(A,'descend'); % sorted from max to min [~,indx] = unique(Asorted); equalp...

Sorting from the maximum value to minimum value in a vector

A=[2 5 8 7 8 9 3 7 6 5 4 1]; Asorted = sort(A,'descend'); % sorted from max to min [~,indx] = unique(Asorted); equalp...

2 years ago | 0

| accepted

Answered

Setting similar scale for two graphs

You need to use |plot(x,y)| instead of |plot(y)|, where |x| is the vector of x-values at which you want to plot |y|. For example...

Setting similar scale for two graphs

You need to use |plot(x,y)| instead of |plot(y)|, where |x| is the vector of x-values at which you want to plot |y|. For example...

2 years ago | 0

Answered

ANOVAN with possibility of matrix as an input (columns as the variables)

The complex syntax of |anovan| allows you to handle the case of unbalanced data. Since you have the same number of observations ...

ANOVAN with possibility of matrix as an input (columns as the variables)

The complex syntax of |anovan| allows you to handle the case of unbalanced data. Since you have the same number of observations ...

2 years ago | 0

| accepted

Answered

One-tailed test using the ranksum function

Your premise that "we should always get h=0, irrespective of the value of ‘alpha’" is not correct. Please see the definition of...

One-tailed test using the ranksum function

Your premise that "we should always get h=0, irrespective of the value of ‘alpha’" is not correct. Please see the definition of...

2 years ago | 0

Answered

Plot det(matrixA - (x * eye(3))) where x = 0:3

You want to do this for each value of |x|, so |x| must be treated as a scalar, not as a vector. A = rand(3); % do for some ...

Plot det(matrixA - (x * eye(3))) where x = 0:3

You want to do this for each value of |x|, so |x| must be treated as a scalar, not as a vector. A = rand(3); % do for some ...

2 years ago | 0

| accepted

Answered

Why am I getting such a large number on the initial iteration?

The problem is that you are overwriting the variable |n| inside the loop, so it changes value from |100| to |10|. Changes: ...

Why am I getting such a large number on the initial iteration?

The problem is that you are overwriting the variable |n| inside the loop, so it changes value from |100| to |10|. Changes: ...

2 years ago | 0

Answered

row of all 8’s

N = 10; X = ones(N); % create a matrix of 1s X = [X(1:N-3,:) ; 8*ones(1,N) ; X(N-2:end,:)]; % add a row of 8s between (N...

row of all 8’s

N = 10; X = ones(N); % create a matrix of 1s X = [X(1:N-3,:) ; 8*ones(1,N) ; X(N-2:end,:)]; % add a row of 8s between (N...

2 years ago | 0

| accepted

Answered

working out acceleration from 2 matrices- HELP

It is not correct to put a |0| when you don't know the value of acceleration. Instead, you should define a new vector of time po...

working out acceleration from 2 matrices- HELP

It is not correct to put a |0| when you don't know the value of acceleration. Instead, you should define a new vector of time po...

2 years ago | 0

Answered

How can I make an array of handles?

You don't need an array of handles to do that. You can use arrayfun like this: x = 1:5; y = 5; z = arrayfun(@(x,y) 3*...

How can I make an array of handles?

You don't need an array of handles to do that. You can use arrayfun like this: x = 1:5; y = 5; z = arrayfun(@(x,y) 3*...

2 years ago | 0

Answered

Adding noise to EEG dataset

I assume you're getting an error in this line: X = dataset + 2*randn(size(t)); because |dataset| is an |N x 2| array, wh...

Adding noise to EEG dataset

I assume you're getting an error in this line: X = dataset + 2*randn(size(t)); because |dataset| is an |N x 2| array, wh...

2 years ago | 0

| accepted

Answered

Multiplying part of vector with another vector repeatedly without for loop

Try using |repmat|: s = sequence(:).*repmat(carrier(:),N,1); % N is the no.of 10-element segments in 'sequence'

Multiplying part of vector with another vector repeatedly without for loop

Try using |repmat|: s = sequence(:).*repmat(carrier(:),N,1); % N is the no.of 10-element segments in 'sequence'

2 years ago | 0

| accepted

Answered

How can I deal with missing data ?

What kind of calculations are you doing? For basic operations such as |sum|, |mean|, |std|, |max|, |median| etc., you can use...

How can I deal with missing data ?

What kind of calculations are you doing? For basic operations such as |sum|, |mean|, |std|, |max|, |median| etc., you can use...

2 years ago | 0