Question

cputime() related question

Just a quick question is there a difference between t1 = cputitme(); t2 = cputime(); t = t2 - t1 and t1 = cputtime(); t...

2 maanden ago | 0 answers | 0

Question

Perform processing over each row of table starting from first non-zero element in that row

Hello is there a way to perform mean and movmean of each row of the table starting from its first non zero element?

3 maanden ago | 1 answer | 0

Question

How do we do operations directly on table elements in matlab?

I am thinking of doing min max normalization of my data where if x is vector the procedure is as follows x = (x- min(x))/(max(x)...

3 maanden ago | 2 answers | 0

Question

How do we rotate two different image objects at the same time in a plot

so lets say I have a 3D surf plot with three different surface objects s1, s2, s3 is it possible to use rotate function to rota...

4 maanden ago | 1 answer | 0

Question

Why hough transform is detecting only 1 horizontal line in the image ?

Here is my code: sx_norm = sx/max(sx(:)); sx_norm = movmean(sx_norm,5,2); %remove discontinuities by moving average N = size(...

6 maanden ago | 1 answer | 0

Question

How do I apply a window on an image to keep the part in the window while reduce the resolution (clarity) of the remaining part of the picture?

Suppose I have an image with three circles and a line as shown below. I want to apply a trapezoidal type window (see dotted line...

6 maanden ago | 1 answer | 0

Question

Simplifying complex multiplications by means of polar coordinates

I have a complex matrix A of size and another complex matrix P that has same size as A. But abs(P) = ones(size(M,N)) which ind...

7 maanden ago | 1 answer | 0

Question

parallel execution of loop

I have the following structure for i = 1:N %some lines of code for j = 1:M %some line...

meer dan een jaar ago | 0 answers | 0

Question

How to add two images excluding simalar elements

The figure below shows two images and their addition. Is there a simple code or a function to avoid adding the highlighted area ...

meer dan een jaar ago | 1 answer | 0

Question

Find the interval of an envelope corresponding to a specific peak after peak detection

I have done the peak detection to find the highest peak in the image below. How do I find the interval of the envelope correspon...

meer dan een jaar ago | 1 answer | 0

Question

find peaks in a mesh plot

How do I find peaks in a mesh plot and also find its location on the mesh grid?

meer dan een jaar ago | 2 answers | 0

Question

Thresholding based on energy

I have an image which is very sparse. I want to threshold the image by retaining a certain amount of energy. What is the most ef...

meer dan een jaar ago | 1 answer | 0

Question

Is it possible to perform multiplication and update 'val' inside accumarray?

An accumarray function is defined as A = accumarray(subs,val,sz) I am running accumarray function in a loop , Is it po...

ongeveer 2 jaar ago | 0 answers | 0

Question

Is there a function that performs element by element multiplication between two variables and stores in one of the variable by default?

I want to do this operation A = A.*B; Is there a function func(A, B) that multiplies A and B and saves the res...

ongeveer 2 jaar ago | 2 answers | 0

Question

Summing of non-zero elements of columns using indexing

I have idx, is there a way of using idx to make the sum(matrix,1) in the below code cheaper. In another words, is it possible to...

ongeveer 2 jaar ago | 2 answers | 0

Answered

HI friends, I need a matlab code of economic load dispatch with loss.

Here is one code which I found https://www.mathworks.com/matlabcentral/fileexchange/49456-economic-dispatch-including-losses He...

HI friends, I need a matlab code of economic load dispatch with loss.

Here is one code which I found https://www.mathworks.com/matlabcentral/fileexchange/49456-economic-dispatch-including-losses He...

ongeveer 2 jaar ago | 0

Question

is there any faster way to operate a group of statements in a loop only once, than applying if else

for ......... statemets 1; statements 2: if iteration == 0 [value1,value2] = function(args1,args2); %dependent on ...

ongeveer 2 jaar ago | 1 answer | 0

Answered

How can I make derivatives with several variables?

You can try this a = a1^2*a2^2; diff(a,a1) + diff(a,a2); ans = 2*a1^2*a2 + 2*a1*a2^2

How can I make derivatives with several variables?

You can try this a = a1^2*a2^2; diff(a,a1) + diff(a,a2); ans = 2*a1^2*a2 + 2*a1*a2^2

ongeveer 2 jaar ago | 1

Question

Sparse for element by element operation

If we want to perform the product of two sparse matrices or sparse and a full matrix , sparse function is very useful as it avoi...

ongeveer 2 jaar ago | 2 answers | 0

Question

Sparse and binary mask

I am working on saving computations and speeding up my Matlab code. Here's what I do Perform thresholding on an image and mak...

ongeveer 2 jaar ago | 3 answers | 0

Question

saving multiplications with zeros in a loop

%if true for i iterations Matrix = Matrix.*phase %Matrix has lot of zeros I want to skip multiplications with zero. Is it po...

ongeveer 2 jaar ago | 1 answer | 0

Question

convert whole code to double

is it possible by anyway to convert whole code to double in a single step? For operations such as sparse single format and integ...

ongeveer 2 jaar ago | 1 answer | 0

Question

Calculate values only once in the loop

Suppose I have a code running in a loop I have done some operations and I create a matrix in the loop, that matrix has the sam...

ongeveer 2 jaar ago | 2 answers | 0

Question

can anyone tell me an intuitive way of finding number of bins for histcounts function

The binning algorithm used by matlab is very expensive [N,edges] = histcounts(I) Instead I am looking for some different and co...

ongeveer 2 jaar ago | 1 answer | 0

Question

why does method 1 result not equal to method 2 result even if both perform the same thing ?

a = [2 5 2 9 ; 3 2 5 0; 4 5 9 2; 1 6 1 5] threshold = 3 %function 1 z = 0; for n = 1: size(a,1) for m = 1...

ongeveer 2 jaar ago | 1 answer | 0

Question

How do I threshold the image automatically based on its energy content?

Say my threshold is taking in those components that constitute about 75% of energy of image and making the remaining as zero.How...

ongeveer 2 jaar ago | 1 answer | 0

Question

Histogram based thresholding for reduction in computation

i am planning to use histcounts () function for histogram based threshold We know that histogram is a plot of pixel intensity v...

ongeveer 2 jaar ago | 2 answers | 0

Question

Getting values of the histogram without actually plotting it

<</matlabcentral/answers/uploaded_files/130633/Screenshot%20(259).png>> Hello, I am working on automatically adjusting the th...

ongeveer 2 jaar ago | 1 answer | 0

Question

Difference between graythresh and multithresh for one value of threshold.

graythresh(I) and multithresh(I,1) gives me different values even if both are based on otsu's method of thresholding Why?

ongeveer 2 jaar ago | 1 answer | 0

Question

For a loop , to carry out element by element multiplication is bsxfun better than conventional element by element.

for number of iterations A = A.*B; %A and B both are complex end Will the loop be faster if I replace A.*B wit...

ongeveer 2 jaar ago | 3 answers | 1