# All Questions

9 views

### Strange style conversion indicator appeared when type “a Pre”

I got the following strange style conversion indicator when I was typing a Pre(character a and ...
3 views

### finding eigenvectors of a n*n symbolic matrix

is it possible to find eigenvectors and eigenvalues of this matrix in mathematica?i have no idea about solution!please help... ...
53 views

### ParametricNDSolve KKT Constraint Directly

I am trying to directly solve for an optimal control using Pontryagin Maximum, where H is the Hamiltonian, in the presence of a KKT constraint. The constraint is ignored. I am wondering if a direct ...
33 views

### Calendar view outline

How to compute the outline of a calendar month like this D3 example. (D3 is a functional language built on JavaScript developed at Stanford and used by New York Times to deploy interactive ...
24 views

### Where can I put my conditions?

I just learned in this answer that you can put conditions inside a With and thus use computed values in them, like this: ...
4k views

### Circuit drawing in Mathematica

This past semester I taught an introductory electromagnetism course and had quite a nice time using Mathematica to draw all sorts of figures and diagrams (mostly for problems and etc.). However, I was ...
15 views

### Find maxima and minima of data like {time,value}

I have a list of time and values of the charge and discharge of a capacitor, and i want to separate in two list of {time,value of charge} , {time, value of discharge} I know there is a lot of the ...
14 views

### How to regress negative log?

I made a regression using Linearmodelfit. The residual-fit plot showed that this was not a good approximation. Now I'm trying to use Nonlinearmodelfit. I assume my data to have a negative log look. ...
102 views

### How to use a compiled function in numerical optimization

I'm trying to wrap my head around function Compile. So, this is a spin-off question from: a previous question on using compile[] correctly. I have a function that ...
37 views

### ComplexExpand does not treat everything as real number

ComplexExpand does not treat everything as real number?? Please read the following simple example ...
30 views

### How can one get rid of the “Template notebook” bar in Mathematica?

Alright, maybe I'm just really stupid. But I tried my damnedest to get rid of this stupid toolbar. I checked every menu and searched google for a solid 20 minutes. Eventually, I just copied the code ...
14 views

### ReplaceRepeated vs DownValues speed

I have to solve a problem by recursive substitution. I programmed it two different ways: using ReplaceRepeated and using ...
8 views

### Error While Doing NIntegrate function

I am trying to calculate this expression in mathematica but I always get 3 errors which are the integrand...has evaluated to non-numerical values for all sampling points in the region with boundries ...
16 views

### Limited Opacity Levels in Image3D?

I'm trying to render a simple spherical distribution where the opacity varies with radius using Image3D. Unfortunately, the outcome is not very appealing, with ...
35 views

### Recursive partitioning: Is there a better way to do this?

Consider the following function, which recursively splits a list into equal length sublists (the length of the list is assumed to be a power of the second argument): ...
45 views

### Mathematica does not calculate inverse fourier transformation or the convolution of two functions

I am trying to take convolution of a Gaussian function with an exponential function. Mathematica couldn't calculate it. ...
13 views

### Combine ImplicitRegion

I have a starting and a target set which I would like to represent via ImplicitRegion. I can evolve each point p of the starting ...
61 views

### My Baum-Welch algorithm is very slow. Is it due to Mathematica?

I've also posted this question here, since I'm not sure which community is more adequate for this type of question. I've programmed imperatively the Baum-Welch algorithm for a 2 state hidden Markov ...
64 views

### Plotting 3D Vector Field in one plane

I want to plot a vector field F={Fx, Fy, Fz}. However, I only want to plot it in one plane (say, z=0). When I use ...
66 views

### Controlling PointSize in a RegionPlot

I have a "named" point in Mathematica 10 and am plotting it like this using RegionPlot: ...
31 views

### How to simplify symbolic matrix multiplication using the associativity of scalar multiplication?

My input is (2A).(3B). Is there a way to get 6A.B? All I could get back from Mathematica was ...
46 views

### Labeling named point in Mathematica 10 [on hold]

I have a "named" point in Mathematica 10 defined like this: point["camp location"] = Point[{latitude, longitude}]; I assume there is some way to make the name of ...
137 views
+200

### Curve fit based on minimal data

Inspired by the fantastic answers here and here, I would like to ask a questions along similar lines. I have 6 curve types that follow these rules: Type A: If point 1 is positive and point 2 is ...
20 views

### Fitting a plane from a set of (x,y,z) values with uncertainties on 3 variables

I would like to fit a plane from a set of measurements (x,y,z) with uncertainties on the 3 variables. Currently I am using the command "LinearModelFit" that computes the best plane but I have a ...
248 views

### How to deal with recursion formula in Mathematica?

In engineering problems, I am always seeing many recursion formula. For instance, In the book "The NURBS book", I discovered many recursion formula Fibonacci ...
57 views

### Select pairs of columns from an array of data

I try to interpolate the first two columns of a seven-column file formatted as follows: ...
28 views

### Retain or delete parts of textstring in tweets

For a twitter analysis I collected many tweets. For example: ...
40 views

### Puzzling NDSolve[] behavior for PDE (smooth solution, inconsistent with boundary conditions)

Consider the following: NDSolve[{D[z[x, y], x, x] + D[z[x, y], y, y] == 0, z[x, 0] == Sin[x], z[0, y] == Cos[y]}, z[x, y], x, y] {{z[x, y] -> ...
115 views

### Triangulated Mesh from Voronoi Diagram

I want to generate a mesh (using Mathematica 10) in the following manner: Generate a Voronoi diagram, like so: and then triangulate each individual Voronoi grain, were an edge is formed by ...
60 views

### How a novice user better understand the Q/A

A novice user reading Q/A here: I sometime need to just understand the syntax and meaning of commands exampled here. where is the best place to find it?
484 views

### Permutations[Range[12]] produces an error instead of a list

This input: Permutations[Range[12]] Results in this (error) output: ...
45 views

### Display solution of Solve without the arrow [on hold]

Is there a way to format Solve or something that I get the result of a calculation without the arrow, so if my result is like ...
4k views

### Finding Local Minima / Maxima in Noisy Data

I'm trying to find local minima / maxima in noisy data, consisting of data values taken at certain time intervals. Ideally, the function should take a pair of lists (one containing time values and one ...
200 views

### Get 'new' list of data by manipulation 'old' list

Assume I have the the following list of data: valuesOld = {5, 10, 15, 20, 25, 35, 40, 45, 55, 65, 80}; I would like to construct the following list: ...
16 views

### WhenEvent: forcing the solution to be non-negative for a system of coupled PDEs

I am newbie in Mathematica, but need to use and modify a code written by another person. The code is solving a system of coupled PDEs (reaction-diffusion system) using ...
49 views

### Why PlotStyle->Dashed make everything dashed?

It has been really strange for me. I am not sure it's regression after v10.0.1, or something went wrong with my system. After running this simple code ...
51 views

### Definite Integral over Bessel Function

Hello I am interested in evaluating the following integral. ...
103 views

### Add text after label in a Manipulate graphic

I can add the value of a slider to the right of it using the Appearance-->Labelled option, but what if I want to add text after the automatic label. How can I do that? Normally I want to do this to ...
43 views

### Spherical parametric plot

How can I plot such a parametrized curve: $r = 2cost + sint$ $\theta = t$ $\phi = sin10t$ where $0<t<\pi/2$. In the documentation only has been discussed parametric plot in Cartesian ...
51 views

### Manipulate with Locator question

Here is an example from Mathematica's help: Manipulate[Graphics[Polygon[pt], PlotRange -> 2], {{pt, {{0, 0}, {1, 0}, {1, 1}, {0, 1}, {1, -1}}}, Locator}] ...
174 views

### Finding totals in a Dataset

I have this Dataset: ...
27 views

### Using variable values from Manipulate in later Plots etc

i wanted to get write something that gives me all the values i want for the Student -t distribution. In my definition i tried to acess the variables, df and t, to later plot how it looks like in a ...
173 views

### A problem about recursion formula of deCasteljau algorithm

I use mathematica to realize the deCasteljaul algorithm $$\vec{P}_{k,i}(u_0)=(1-u_0)\vec{P}_{k-1,i}(u_0)+u_0\vec{P}_{k-1,i+1}(u_0)$$ The graphics that deCasteljaul algorithm generated as below: ...
14 views

### Changing default behavior of Series to give slightly different SeriesData

I am working with complicated expressions expr which contain symbolic function the f[x] which I know to have a pole at ...
64 views

### Numerical Integration

I have used the following code to evaluate an integral (val) numerically ...
25 views

### Replacing variable names in a notebook

I am working on a code that simply imports and graphs a function. If I preset the directory I would have something that looks like this: ...
69 views

### Why does BernsteinBasis not plot correcly?

I want to use the built-in function BernsteinBasis to learn about Bezier curves. I tried the following: ...
108 views

### How can I read compressed .Z file automatically by Mathematica?

When I read .Z file by something like jpldatstring = Import["ftp://cddis.gsfc.nasa.gov/products/jpl/2003/jplg0040.04i.Z"] Unfortunately, it turned out that ...