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Use two bsxfun for row and column vector to span matrix without putting in memory
Hello, I have a vector A of size 1xN and a vector B of size MxN I can span a MxN matrix temp with temp=bsxfun(@times,A,B);. ...
7 years 前 | 1 个回答 | 0
1
个回答提问
Efficiently calculate distance between moving point and fixed points
Hello, I have a grid of point coordinates xval=0:1:5000; yval=0:1:2000; zval=1; [X,Y,Z]=meshgrid(xval,yval,zv...
7 years 前 | 1 个回答 | 0
1
个回答提问
Better interpolation of nonuniform data to uniform grid than with spline
I am resampling non-uniformly sampled data to a uniform grid with a spline interpolation. However, if the signal is of high fre...
7 years 前 | 0 个回答 | 0
0
个回答提问
Speed up 1D spline interpolation on matrix
Hello, I have a NxM matrix named data and I need to spline interpolate each row of my matrix according to: for k=1:size(...
7 years 前 | 1 个回答 | 0
1
个回答提问
ned2ecef without toolbox
Are there any user-made functions available somewhere that achieve the same? The lg2ct function in the Geodetic Toolbox on the ...
7 years 前 | 0 个回答 | 0
0
个回答提问
Multiply each column in MxN matrix with it's transpose to create MxMxN matrix
Hello, I have a MxN matrix, and I need to multiply each column vector that is of size Mx1 with it's transpose. This gives me...
7 years 前 | 2 个回答 | 0
2
个回答提问
Interpolate uniform to non-uniform sampling, artifacts with spline
Hi, I have to resample uniformly sampled data to a non-uniform sampling. I use the spline function for this, and if the sample...
7 years 前 | 0 个回答 | 0
0
个回答提问
Merge multiple GPS and IMU to get more accurate position and attitude
I have multiple GPS and IMU that are located at known positions of an aircraft. Is there a ready to use implementation to merge...
7 years 前 | 0 个回答 | 0
0
个回答提问
Best way to smooth GPS data
Hi, I have a GPS signal sampled at 1Hz. It is too noisy, so I want to smooth the signal. I tried using a moving average, but i...
7 years 前 | 3 个回答 | 0
3
个回答提问
reshape, remove 16 elements, keep 1000*8, remove ..
Can I solve this without a loop?/What is the fastest way? I have a long vector consisting of [16Elements 1000*8Elements 16Eleme...
7 years 前 | 1 个回答 | 0
1
个回答提问
Calculate only fraction of spectrum with FFT
I have a signal with 4096 samples. I can calculate the frequency spectrum of this signal with fft. But I am only interested in...
7 years 前 | 1 个回答 | 0
1
个回答提问
Speed up this fread loop
I need your help! I am going to read a lot of big files with fread. Any ideas on how to speed this up? Also if there is a way ...
7 years 前 | 2 个回答 | 0
2
个回答提问
Matrix indexing: fast way to compute covariance of N different MxL matrices that are saved in NxMxL matrix
I have a NxMxL matrix called bigmatrix That I can split into N temporary submatrices. On each temporary submatrix I need to ca...
7 years 前 | 1 个回答 | 0
1
个回答提问
IFFT calculate only one timesample
I have a frequency signal and I apply an IFFT to it. This results in the time domain x(n) which has N samples. But I am really...
7 years 前 | 1 个回答 | 0
1
个回答提问
Combine multiplication filter in time and frequency domain
Hello, I perform a FFT on my signal x, which yields X. Then I perform a multiplication in the frequency with my filter W, whic...
7 years 前 | 1 个回答 | 0
1
个回答提问
bsxfun to multiply matrix with vector multiple times in for loop --> how faster?
I have a 2D matrix of size NxN, and each row I am multiplying with a 1xN vector with bsxfun in a for loop like this: for k=...
7 years 前 | 2 个回答 | 0
2
个回答提问
How to vectorize loop with linspace for performance
Besides prelocation my matrix A, how can I save time here? for k=1:1:10000 A(k,:)=firstValue(k):fixedStep:lastValue(k); ...
8 years 前 | 1 个回答 | 0
1
个回答提问
Fast Look-up table
Good morning, I have a long array signal with values x. Now for each of those values x I want to find the closest fit in anoth...
9 years 前 | 1 个回答 | 0
1
个回答提问
Highly interpolate complex spectrum
Good afternoon, I have a complex spectrum of a signal that is centered around a center frequency with a certain bandwidth. I...
9 years 前 | 0 个回答 | 0
0
个回答提问
Highly oversample FFT2 in one direction for peak detection
Hello, I have a 2D image and the resulting FFT2 has high peak. Now I can find the maximum to get the resulting peak shift in e...
9 years 前 | 0 个回答 | 0
0
个回答提问
Translate position uncertainty of two objects to uncertainty of distance between them
Hello, I have a plane and in this plane there are two objects. The real location of each object is somewhere in the circle o...
10 years 前 | 0 个回答 | 0
0
个回答提问
Probability of two adjacent cells being below gaussian percentile
Hello, I have a matrix, whose data is described by a gaussian curve. Now I have a probability of 8%, that the data falls below...
10 years 前 | 1 个回答 | 0
1
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Precision when dividing two functions going against zero
Hi, I have two functions A=sinc(c1*x)-cos(c2*x) whichs is Zero for x=0. Now I want to calculate A/(c3*x). The expected result...
10 years 前 | 2 个回答 | 0
2
个回答提问
Image from Gradient and Magnitude
Hello, with imgradient I can compute the magnitude and direction of an image's gradient. Is it also possible to somehow comput...
10 years 前 | 1 个回答 | 0
1
个回答提问
Height difference between earth models
Hello, is it possible to calculate the height difference between earth models at specific points of lat and long? For example ...
10 years 前 | 0 个回答 | 0
0
个回答提问
rectangularPulse: no drop to 1/2 at edges
Hello I want to do the fourier of a rectangular pulse which is also 1 at the edges, so that the fourier returns a sinc function...
10 years 前 | 2 个回答 | 1