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error in a function, Error: In an assignment A(I) = B, the number of elements in B and I must be the same.
I have defined a piecewise function (below), where C1 (and hence x) is a vector. I don't understand why the error "In an assign...
7 years 前 | 2 个回答 | 1
2
个回答提问
How to solve error in pdepe
I'm using pdepe to solve a parabolic pde in (x,t). I'm getting an error for times bigger than 0.3, though it works fine for smal...
8 years 前 | 1 个回答 | 0
1
个回答提问
choose line color based on intensity
Hi, I have a plot with several concentric circles, and a vector C which gives a value for each radius used. I would like each...
9 years 前 | 2 个回答 | 0
2
个回答提问
transforming matrix after change of variables
Hi, I have a matrix M(r, t), which I would like to transform into a matrix N(x, y, t), where x = r*cos(theta), y = r*sin(thet...
9 years 前 | 2 个回答 | 0
2
个回答提问
Nonlinear parabolic PDE with PDE toolbox
Hi, I'd like to solve the PDE $\partial u / \partial t = r*(\partial/\partial r[r*D0*(u/u0)^n])$ where D0, C0 and ...
9 years 前 | 1 个回答 | 0
1
个回答提问
VideoWriter Axes and title
Hi, I'm using VideWriter to create a video of the progress of the profile of a solution to a PDE. I would like the video to a...
9 years 前 | 1 个回答 | 0
1
个回答提问
Why am I getting this error?
I'm using pdepe and I keep getting the error "Error using pdepe (line 293) Spatial discretization has failed. Discretization sup...
9 years 前 | 1 个回答 | 0
1
个回答提问
Fisher reaction PDE propagating from a point source
Hi, I'm using pdepe to solve the nonlinear hear equation $\frac{\partial C}{\partial t}=r^{1-s}\frac{\partial}{\partial r...
9 years 前 | 0 个回答 | 0
0
个回答提问
PDE compact solutions in Matlab
Hi! I'm working on solutions to a parabolic PDE, and was wondering if there is a way to get MATLAB to work out whether the so...
9 years 前 | 1 个回答 | 0
1
个回答提问
Plotting phase plane from system of second order ODEs
Hi, I'm using ode45 to solve a system of two second order ODEs (writing it as a system of 4 first order ODEs) du(1) = u(3)...
9 years 前 | 1 个回答 | 0
1
个回答提问
student license on two computers
Hi, I would like to be able to use my student Matlab license in my personal computer as well as my laptop. Is this possible? Ho...
9 years 前 | 1 个回答 | 0
1
个回答提问
Saving movie of solution profile
Hi, I'm creating a figure to see the progression of a solution in time: figure fig = plot(r, u(1,:), 'erase', 'x...
9 years 前 | 1 个回答 | 0
1
个回答提问
PDE propagating from point source
I want to solve numerically a nonlinear diffusion equation from an instantaneous point source. Thus, I have initial conditions, ...
9 years 前 | 1 个回答 | 0
1
个回答提问
solving non-linear ODEs algebraically with symbolic math toolbox
Hi! I'm trying to solve a second order nonlinear ODE for $u_n(t)$, and I have this code: clear all n = sym('n'); p = s...
9 years 前 | 1 个回答 | 0
1
个回答提问
awgn function - how does it add signal-to-noise ratio
Hi, I've been using the function awgn to add white gaussian noise to some synthetic data. I need to know exactly how this is ...
9 years 前 | 0 个回答 | 0
0
个回答提问
changing scale of x-axis in histfit
Hi! I am generating some histograms with a normal distribution using histfit, and I need to change the scale in the x-axis. S...
9 years 前 | 1 个回答 | 0
1
个回答提问
sampling pairs of elements
Hi, I'm trying to sample data from two vectors simultaneously, one is a population value and the other a point in time. I nee...
9 years 前 | 2 个回答 | 0
2
个回答提问
histogram of iterated values
Hi, I have a program that estimates a parameter from data with random noise. Since the noise is random, the estimate is diffe...
9 years 前 | 1 个回答 | 0
1
个回答提问
ignoring imaginary parts when plotting
Hi, I have a program that estimates some parameters and then plots a curve using those estimates. The parameters are estimate...
9 years 前 | 1 个回答 | 0
1
个回答提问
checking if values are equal in a loop
Hi, I have a program that estimates some parameters iteratively and returns the value after a set number of iterations of a f...
9 years 前 | 1 个回答 | 0
1
个回答提问
iterations required for parameter convergence
Hi, I have a code that uses an iteration algorithm to estimate some parameters. Is there a way to get it to iterate until the...
9 years 前 | 1 个回答 | 0
1
个回答提问
histogram of error distribution
Hi, I have a set of data to which I am adding weighted random error from a uniform distribution, and I would like to generate...
9 years 前 | 1 个回答 | 0
1
个回答提问
Finding average of iterated curves
I have a code that generates multiple curves from a set of data that gets random error added to it, so after each iteration of t...
10 years 前 | 1 个回答 | 0
1
个回答提问
why do i get the error: matrix dimensions must agree ??
this is what I'm trying to plot x=linspace(0,100,100); a=5; y=1/(abs(a*x)+1); figure plot(x,y) how do I fix th...
10 years 前 | 1 个回答 | 0
1
个回答提问
keep getting error in the covariance: Subscript indices must either be real positive integers or logicals.
I keep getting this error in calculating the covariance between two variables, how should I do it to avoid the error? Subscri...
10 years 前 | 1 个回答 | 0