MATLAB is a high-level language and interactive programming environment for numerical computation and visualization developed by MathWorks. MATLAB can be used when performing tasks such as signal processing and communications, image and video processing, computational finance, and computational ... ...

learn more… | top users | synonyms

1
vote
0answers
838 views

The phase portrait of a second order of nonlinear system using matlab

I have the following system $$ \ddot{x} + 0.6\dot{x} + 3x + x^{2} = 0 $$ In the book I'm reading, the phase portrait of the nonlinear system for the aforementioned equation is I would like to ...
0
votes
1answer
90 views

symbolic definite integral using matlab

I have this function $$ \frac{di}{dt} = - \frac{R}{L} i $$ I know the solution which is $$ i(t) = i_{0} e^{- \frac{R}{L} (t-t_{0})} $$ I would like to get the same solution by using Matlab. How can ...
1
vote
0answers
106 views

implicit non-linear equations with complex variables

I am trying to understand a methodology for solving implicit non-linear equations with complex variables. I would like to solve for z1 below where z2 is known. Also both z1 and z2 are complex ...
0
votes
1answer
44 views

Inequality involving fractions and several variables

Based on my previous two questions (that failed), I am trying once more. What are some simplified conditions for which: ...
1
vote
0answers
61 views

Time needed to algebraically solve system of $15$ nonlinear equations with parameters

How long can I expect it will take to algebraically solve a system of $15$ nonlinear equations (without any numbers, only parameters), if I feed it into a computing software? I'm asking for symbolic ...
-1
votes
1answer
52 views

correlation matching audio files peak position

if i cross correlate an audio file with itself (which means there is no delay or difference), the peak position should be a zero or at the center of the cross correlation? that is really confusing ...
0
votes
0answers
124 views

How to get this formula in fv tool (Matlab)?

I have this formula $$\frac{z^{-4799}-0.742}{0.742z^{-4799}}$$ I know that the fv tool can plot diagrams from this but I don't know how to get them in there. Any tips?
0
votes
1answer
79 views

Matlab: integrate function in dependence of a parameter

I am a matlab beginner and can not spot the mistake in the following code: ...
1
vote
1answer
231 views

Generate random numbers with a modified PERT distribution

I want to generate random numbers based on the modified PERT distribution. The modified PERT distribution is a special case of the beta distribution and is defined as: $$f_X(x) = ...
0
votes
1answer
42 views

Anyone recognize this pattern? Plotting relationship between two parameters and their response.

First time asking a question here so hopefully I can provide enough information to you guys without explaining more than necessary. I'm doing some amateurish numerical analysis in MATLAB on some ...
2
votes
1answer
98 views

Fourier series of oscillation in form $\cos(2 \pi \frac{k}{T}+\phi)$

I would like to calculate the fourier coefficients of $\cos(2 \pi \frac{k}{T}+\phi)$ where $T \in \mathbb{N}$ is the period and is arbitrary but fixed, $k \in [1, N-1]$ is the number of oscillations ...
0
votes
1answer
34 views

Sorting and removing data in MATLAB

I am new to MATLAB and I have to analyze a file containing lighting data from WWLLN. The data file contains: latitude of stroke in first row, and longitude of stroke in second row This file has ...
2
votes
2answers
751 views

Matlab Code to simulate trajectories of Ito process.

I need some help to generate a Matlab code in order to do the following question. Can somebody help me in this regard. Any sort of hint that could be helpful will surely be appreciated.. Q: "Simulate ...
2
votes
1answer
219 views

Differentiation of a parametric function using MATLAB or Maple

I'm doing some mathematical calculation of some symbolic math that includes multiplication and differentiation of some matrices. Some of the parameters in my calculations are functions of time. for ...
6
votes
2answers
364 views

Image Reconstruction:Phase vs. Magnitude

Figure 1.(c) shows the Test image reconstructed from MAGNITUDE spectrum only. We can say that the intensity values of LOW frequency pixels are comparatively more than HIGH frequency pixels. $$ ...
1
vote
0answers
297 views

pdf of an uniform distribution in matlab?

I'm reading a book and I came across a problem in which I should generate a uniform random variable and use hist, mean and std ...
2
votes
0answers
94 views

How to solve this complicated differential equation?

I need to know how to solve this complicated differential equation in $z$ either analytically or numerically : \begin{eqnarray} \frac{dx_1}{dz} &=& -ib_1x_1 - ikx_2 \\ \frac{dx_2}{dz} ...
0
votes
1answer
55 views

How to solve these two differential equation?

I try to solve these two difference equation ; $$ \frac{dq}{dz} = -j\left(b_1q - kp\right),\\ \frac{dp}{dz} = -j\left(b_2p - kq\right) $$ where $j$ stands for $\sqrt{-1}$, and $b_1$ ,$b_2$ and k are ...
3
votes
7answers
457 views

Best Math Plotting Software for Electrical Engineering

I am an electrical engineering undergrad. I would like to learn a math plotting software which would be helpful in visualizing topics in advanced calculus (my immediate need). It would also be helpful ...
1
vote
0answers
128 views

what does autocorrelation matrix signifies in image processing?

I am trying to find out corners using auto correlation matrix in an image,what does it signifies?
3
votes
0answers
38 views

what is the significance of Eigen values of autocorrelation matrix?

I am trying to find auto correlation matrix of an image to get Harris corners.Paper I am referring suggest that if eigen values of auto correlation matrix are large the point will be corner point.so ...
0
votes
1answer
367 views

How to add standard deviation regarding MATLAB function normrnd(mu,sigma)?

My question depend on this scenario which is as follows, I used a MATLAB function "normrnd(mu,sigma)" with mean 'mu = 0' and S.D 'sigma = 5', to generate a normal random number "R1". I added this ...
1
vote
0answers
37 views

Matlab Optimization problem with Matrices

I'm trying to solve an optimization problem in Matlab. The expressions you will find below. Problem is it is all matrices, and I have no idea which solver to use for that. $w$ is of size $n \times 1$, ...
3
votes
1answer
162 views

Using Monte Carlo method to estimate the value of $\int_0^1\int_0^1e^{xy} \ dx \ dy$

Monte Carlo, estimate the value of $$\int_0^1\int_0^1e^{xy} \ dx \ dy.$$ I am using matlab to solve this problem. My code is the following: ...
3
votes
0answers
89 views

How can I find a tranformation matrix/Mathematical relation between two 5th degree polynomial curves in space?

I have the equation of two 5th degree polynomials which they don`t intersect with each other .Each curve is made of 100 points and these two curves looks similar but there are small differences .I am ...
0
votes
2answers
59 views

plotting two graphs in matlab

it's been 5 hours and I'm trying to plot two graphs in matlab but in vain, here is my code ...
0
votes
2answers
29 views

calculate principal components

suppose that we have following data ...
0
votes
0answers
172 views

Finding minimum of a distance function using matlab

I have a function for that I want to find the minimum. The function calculates the distance between two sets where a set is defined as matix of row vectors $ D = [ d_1, d_2, ..., d_n]$, $d_n$ is a $m ...
0
votes
1answer
2k views

Newton-Raphson Method for Non-linear System of 3 variables in Matlab

I am trying to solve 3 non-linear system of 3 variables using the newton-raphson method in matlab. Here are the 3 non-linear equations: \begin{equation} c[\alpha I+ k_f+k_d+k_ns+k_p(1-q)]-I \alpha =0 ...
0
votes
0answers
43 views

Multivariate Multiple Regression with Repeated Measures

I have a dataset with p predictors for i items (so multiple regression). For each of s subjects, I have r repeated observations of v dependent variables (so it's a multivariate problem). I wish to ...
-1
votes
1answer
224 views

Multiple echo FIR Filter in Matlab [closed]

This is my final homework for the semester, I would be glad if you can help me.
0
votes
1answer
1k views

Evaluating double integrals using monte carlo methods in matlab.

I used the monte carlo method to integrate $\int_{0}^{1}x^2dx$ in matlab. My matlab code was simply the following: A=1; N=10000; s=0; for i=1:N x=rand; y=rand; if y<= x^2; ...
1
vote
1answer
303 views

Determine frequency response from impulse response

I'm studying signal processing, using MATLAB to plot filter responses. So far, I understand I can use the impulse response to apply a filter to a signal. For example, the impulse response of an ...
0
votes
0answers
31 views

I was wondering if there was a way to plot a vector field and a 3d surface in the same window

I want to plot the vector field $$\textbf{F}(x, y, z) = \sin(xyz)\textbf{ i }+ x^2y\textbf{ j }+ z^2e^{x/5}\textbf{ k }$$ And the surface (part of elliptic cylinder) $$\textbf{r}(u, v) = u\textbf{ i ...
0
votes
1answer
34 views

Function with 2 outputs

I have written the following code: function [ z,a ] = complx( numb ) z=abs(numb); a=angle(numb); end but I get back just z and not a
-2
votes
1answer
381 views

Matlab optimization toolbox vs. CVX solver?

I would like to know what is the difference between the Matlab optimization toolbox and CVX solver which is a convex optimization toolbox? Can a convex optimization be solved in both?
1
vote
1answer
235 views

Simpson's composite rule rate of convergence.

Hello I have wriiten a program in Matlab that determines an Integral using Simpsons rule and it also determines the rate of convergence. I tried my program on the following examples: $f(x)=\sin{ x}$ ...
1
vote
0answers
69 views

Bode plot of an unstable system?

I am a bit confused on how to sketch a bode plot for an unstable system? (being a/all pole(s) lies on RHP). I tried plotting it in matlab, but it doesn't resemble the output i was expecting using ...
0
votes
1answer
1k views

MATLAB: Plotting the inverse Fourier transform of a rectangular pulse.

I'm trying to repeat the results in the image below without using the rectangularPulse(a,b,z) function: Here is my unsuccessful attempt: Here is the code I used to create the first image: ...
1
vote
1answer
118 views

Cyclotomic Cosets and Minimal Polynomial for 45

Currently I am working on matlab in order to find Cyclotomic Cosets for 45. As 45 in not in the format of 2^m-1, matlab give me an error. I am trying to write algorithm in matlab/octave for my ...
7
votes
1answer
419 views

Fast algorithm for approximating Eigenvalue distribution of large sparse matrix

I am interested in the eigenvalue distribution of a huge $2^{16}$x$2^{16}$ Hermitian sparse matrix with spectrum contained in $[-1,1]$. That is I don't need to know all eigenvalues exactly, but rather ...
1
vote
1answer
703 views

arc length parameterization of planar curve in Matlab

Let $\gamma (t)$ be a planar curve parameterized by time $t$. For fun, let it be a limacon. In Matlab $\gamma (t)$ looks like this. ...
0
votes
2answers
105 views

Numerical precision of product of probabilities (normal CDF)

I'm trying to calculate $\prod_k{p_k}$ where $p_k$ are (potentially) very high probabilities of independent, zero-mean, standard normal random variables and $k>100$. However, I'm running into ...
1
vote
1answer
286 views

Solving Differential Equations theoretically and using matlab

i am trying to solve the initial value and elliptic boundary value problems below. but now i need some help solving them using matlab. for the elliptic problem, any method is ok, but for the initial ...
2
votes
2answers
317 views

Find the sparse representation in matlab

I have a dictionary(Matrix) D and an input(Vector) Y. Now I want to solve this problem: What is the Sparse Representation of input Y according to dictionary D. this problem is an important question ...
1
vote
3answers
1k views

Using loop to approximate pi (Monte Carlo, MATLAB)

I've written the following code, based on a for loop to approximate the number pi using the Monte-Carlo-method for 100, 1000, 10000 and 100000 random points. ...
0
votes
1answer
98 views

Plot as you go in MATLAB

I'm self studying some numerical analysis and I'd like to get a feel for how an ODE solver speed varies as you move forward in time. Is it possible to use matlab to numerically solve an equation ...
0
votes
2answers
164 views

Solving 2nd degree ODE with Euler method in MATLAB

I am trying to solve the equation below; $$\ddot{x}= -x + sin(t)$$ by the initial conditions; $$x(0) = 0 \\ \dot{x}(0)= 0$$ my MATLAB code is as follows: ...
1
vote
0answers
100 views

Calculating MSE for two different size matrixes

I have two $2$-column matrixes, one of the has $467$ rows while the other one has $61468$ rows. Both them are trajectory paths of same robot, the big matrix is kind of raw data and the smaller one is ...
1
vote
2answers
105 views

trigonometric interpolation of a sampled signal

Given N sampled points, using the FFT we can get the Fourier transform of those N points $X_k$. With N/2 the Nyquist frequency and $X_0$ the DC value. Using the inverse we can then get back the ...