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Compare each row of a matrix with the remaining ones
I have a matrix A of zeros and ones with dimension BxM. Specifically, A contains all the possible dispositions of ones and z...

7 years ago | 0 answers | 0

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answers

Question


Saving in txt format in Matlab with commas and semicolons
I have a huge matrix in Matlab that I want to save in .txt format (or in any other text format). Suppose the matrix is ...

9 years ago | 1 answer | 0

1

answer

Question


Saving/Working with variables using loop index?
Hi, I have some problems with the following piece of code in indexing the names using the loop index. Could you help me? ...

9 years ago | 1 answer | 0

1

answer

Question


Several draws from multivariate normal distribution
Let MU=[1 2; 3 4; 5 6] SIGMA=[2 0; 0 2] I want to write one or two lines of code to draw R=10 unobservables from Norm...

9 years ago | 2 answers | 1

2

answers

Question


How to compute frequency of rows for submatrices?
I have a matrix D which is a concatenation of 4 matrices of 3 rows (breaks added for clarity). I would like to construct a matri...

9 years ago | 2 answers | 0

2

answers

Question


How to construct a binary matrix reporting 1 in case of equal rows of two arrays of different dimensions?
Hi, I have a matrix nxk A=[ 1 2; 3 4; 5 6; 7 8] and a matrix B mxk (m can be > = or < n) B=[ 2 3; 4 5; 1 2; 5 6; 1...

9 years ago | 2 answers | 0

2

answers

Question


How to create a matrix of four dimensions in which the fourth dimension is not fixed?jkjsdfhlksdjhf
Hi, I would like to create a matrix of four dimensions, in which the last dimension is not fixed, in the sense that: suppose ...

10 years ago | 1 answer | 0

1

answer

Question


How to repeat the rows of a matrix by a varying number?
Hi, I have a matrix A mxn and a matrix B mx1. I want to create a matrix C which repeats each row of A by the number of times ind...

10 years ago | 2 answers | 0

2

answers

Question


Generate three dimensional arrays using mvnrnd in Matlab?
I need to generate a three dimensional matrix B in Matlab using the command mvnrnd. In particular, let mu=[0 0; -1 -3; 0 4...

10 years ago | 1 answer | 0

1

answer

Question


Counting subrows in each row of a matrix?
Hi all, I need an algorithm which counts how many adjacent and non-overlapping (1,1) I have in each row of a matrix A mx(n*2) w...

10 years ago | 2 answers | 0

2

answers

Question


Numbering the rows of a matrix giving the same number to equal rows?
Hi all, I have a matrix A mxn with some equivalent rows; the equivalent rows can only be adjacent. I want to create without loo...

10 years ago | 1 answer | 0

1

answer

Question


Algorithm which swaps the columns of a matrix A mx(n*2) without looping?
Hi all, I need an algorithm which swaps the columns of a matrix A mx(n*2) without looping in the following way: %if A=[col...

10 years ago | 1 answer | 0

1

answer

Question


Transform algorithm avoiding loops
Hi, I have to transform the following algorithm in an algorithm without loops. Consider a matrix A with the following charact...

10 years ago | 0 answers | 0

0

answers

Question


How to pick the j-th percentile of a vector?
Hi, I have a matrix A nx1, e.g. A=randn(200,1); II want to pick the element of A which is the 25th percentile above the ...

10 years ago | 3 answers | 0

3

answers

Question


How to count how many times each element appears in a vector preserving the order?
I have a matrix A ax1, e.g. A=[5; 5; 5; 1; 4; 4; 3; 3; 3]; I want a vector B of dimension size(unique(A))x1 which shoul...

10 years ago | 1 answer | 0

1

answer

Question


Option 'stable' of the command unique?
I have a matrix A ax1 and a vector B which is obtained as B=sum( bsxfun(@eq, A, unique(A,'stable')') )' E.g. A=[5;...

10 years ago | 1 answer | 0

1

answer

Question


Compare two matrices of different dimensions
I have a matrix B of dimension bx2 and a matrix A of dimension ax5 with the following characteristics: B=[3 1; 3 2;...

10 years ago | 1 answer | 0

1

answer

Question


How can I check whether the strictly positive elements of each row of a matrix are equal?
How can I check whether the strictly positive elements of each row of a matrix are equal? E.g. if A=[0 1 1 2; 0 1 0 1; 3 0 ...

10 years ago | 3 answers | 0

3

answers

Question


How to compare two matrices of different dimensions?
I have a matrix B of dimension bx2 and a matrix A of dimension ax5 with the following characteristics: B=[1 18; 1 19; 3 1;...

10 years ago | 2 answers | 0

2

answers

Question


How to rearrange the rows of a matrix?
Hi, I want to reshape a matrix A of dimension rxc in a matrix B of the same dimension but with rows rearranged following the ind...

10 years ago | 2 answers | 0

2

answers

Question


How to select only some sections of a matrix?
Hi, I have the matrix C=[1 1; 1 2; 1 2; 1 3; 2 4; 2 5; 2 5; 2 6; 3 7; 3 8; 3 9; 3 10; 4 11; 4 12; 4 13; 4 14; 5 15; 5 1...

10 years ago | 2 answers | 0

2

answers

Question


Find the global minimum of a smooth function
I have a smooth non-negative function of a parameter theta (attached) which should be minimized with respect to theta; which sol...

10 years ago | 1 answer | 0

1

answer

Question


Which is the machine precision of Matlab?
Hi all, I have the following problem: I want to find the argmax (not necessarily unique) of a function f(alpha,beta). Under som...

10 years ago | 2 answers | 0

2

answers

Question


How to split a matrix in different sections in a loop?
Hi all, I have to pick a particular section of a matrix A in each iteration of a loop and use that section for getting some resu...

10 years ago | 1 answer | 0

1

answer

Question


Problem with fmincon and many starting values
Hi all, I'm trying to code the following minimization problem using fmincon and many starting values but I get error messages ...

10 years ago | 1 answer | 0

1

answer

Question


How to use fmincon for constrained maximum likelihood?
Hi, I'm trying to solve a constrained minimization problem but I get several error messages. Could you help me in adjusting the ...

10 years ago | 1 answer | 0

1

answer

Question


Why fminunc does not find the true global minimum?
Hi all, I should solve this unconstrained optimization problem (attached). I know that the function has the global minimum at [...

10 years ago | 2 answers | 0

2

answers

Question


How to use fminunc providing gradient and hessian?
Hi, could you help me in making this code (attached) working? Thanks!

10 years ago | 2 answers | 0

2

answers

Question


Why fminsearch does not find the global minimum?
Hi all, I want to minimize the function fun below and I know that it has a global minimum which is par=[1 2 2 3] but fminsearch ...

10 years ago | 1 answer | 0

1

answer

Question


Selecting only some rows of a matrix
Hi, I have a matrix A mxn and I want to select only some of its rows satisfying this criterion: A(i,1)<=1e-03 && A(i,1)>=-1e-0...

10 years ago | 3 answers | 0

3

answers

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