# All Questions

197 views

### How can I mend this broken heart?

Try to evaluate the following code: ...
642 views

### Symbolic solution(s) to generalized Heat equation

Symbolic solution(s) to Heat equation? or more generally,(eventually) Green functions to known PDEs I am interested in variations of the heat equation: or more generally or even more generally ...
237 views

### Possible bug in Dynamic

The code below crashes the Mathematica kernel in version 10 (not in V9) every time I run it on Windows and on Mac OS. I've sent it to WRI, but was told that they could not reproduce the crash. Does ...
35 views

### Conditions in SparseArray

I got confused by {i_, j_} /; in the following code. I didn't see an explanation in the SparseArray documentation. Can anyone ...
37 views

### Calculate geo location based on distance from other locations

Given a list of entities (or GeoPositions) and their distances from a particular location, how do I find that location's ...
79 views

### Utility information using FindGeoLocation in Ver.10

It is possible for some commuters to track the location of their bus, train or tram through a personalised GPS tracking device (e.g.see ...
88 views

### Partial Differential Equation in Parallel

is there any native way to implement multi-core parallel solving of PDE in Wolfram Mathematica? WM 10 now supports Finite Elements Method, but it is actually useless without parallelization. Usually ...
152 views

### Minimize: How to work with specific numeric types

This is a question about the use of symbols in Minimize and how to persuade Mathematica to treat them in a specific way (as integers or rationals) that I have not ...
83 views

### TrueQ returning False on true statement

Why does TrueQ return False on the following? TrueQ[Log[2]/Log[8] == 1/3] (* False *) ...
41 views

### NDSolve: EventAction list specification using Table fails

I have an NDSolve problem that needs a list of a large number of events that are generated programmatically. Here is a simple example that demonstrates the problem on Mathematica 7 and 8 (the versions ...
78 views

### eccentric anomaly expansion equation

I try to use this simple algorithm (paper) to calculate the Eccentric Anomaly expansion: ...
50 views

### Confidence and prediction bands for custom nonlineal for CDF from ProbabilityDistribution

I have a CDF obtained with the code: ...
244 views

### Create a list of random reals

How can I create a list of random pairs $(x,y)$ where $0<y<x<1$ and $x,y \in \mathbb{R}$ ? I can't seem to place that inequality restriction on the random numbers that are generated.
349 views

### Estimate parameters of the state space model

I'm using Mathematica 9 and its Control Systems functionality. I've searched the references extensively but seem not to be able to find any examples of state space model parameters estimation. All ...
42 views

### Zero-order interpolation not going fully around

Connected to this question, I want to do a zero-order interpolation of a bunch of datapoints which is periodic. The code I use is as follows: ...
84 views

### One ChartLegend for multiple charts in Dataset?

Dataset's documentation shows how to leverage GroupBy operator at multiple levels ...
169 views

### Line style thickness differences between Mathematica 9 and 10

I execute the same code in Mathematica 9 and MAthematica 10, and have this different results. ...
95 views

### Minimize loop optimization

I'm new in Mathematica 10. So far, I have a two variable-function and I've use Minimize to find the optimal solution. Nevertheless, I'd like to make a sensibility analysis and study how this optimal ...
59 views

### how to write TableForm expression into file?

Now I have a list stored in data as follows data = {{"Ca", 1, 1, 1}, {"Ca", 2, 2, 2}, {"Ca", 3, 3, 3}} the ...
165 views

### Spike train representation

I have a spike train. The data shows the time at which the neuron fired a spike. I want to plot them like this picture: Here is the data for one spike train which corresponds to the one of the ...
417 views

### How to embed an image into a string?

Note: The bug described in the post is in Mathematica 9, and has been fixed in 10.0. The documentation for String contains the following statements: Strings ...
141 views

### Extrude 2D cross-section to 3D shape with shrinkfactor

I would like to create a 3D shape from extrusion and scaling of a 2D contour. The 2D contour that I have looks like this: and it consists of a bunch of points (here plotted with ...
36 views

### How to correctly use PatternTest (?) [duplicate]

This works fine: {3, -5, 2, 7, -6, 3} /. x_ /; x < 0 :> 0 (*{3, 0, 2, 7, 0, 3}*) and this works fine: ...
679 views

### About generating power series

For an arbitrary function $f(x,y)$ I am defining functions LogMT1 and LogMT2 as follows, ...
118 views

### Geographic background containing both outlines and contours: how?

I would like to create a map which will show lakes and rivers together with elevation contours and contour labels. What is the simplest way to do this with ...
361 views
+50

### Symbolic integration in real domain only ( assumptions and ComplexExpand don't work)

Integrate[m^2/((x - m^2)^2 + y^2), m] mathematica gives me a complex-valued reuslt, but maple 17 gives me what I want. I tried using assumptions, but it doesn't ...
126 views

### How to slice TimeSeries data?

When retrieving curated data, v10 now returns TimeSeries objects. For example, ...
104 views

### How to transpose x and y axes on a LogPlot?

Consider the following simple LogPlot: LogPlot[Exp[x],{x,0,5}] Is there a nice way to switch the axes of a LogPlot? I'm aware that plotting the inverse ...
51 views

### Changing the data indices for a large dataset plotted with ContourPlot

I have a large (square) dataset that I am plotting with ListContourPlot ... The data is 128x128 -- without coordinates for each point. I.e. - {{0,0,1,0,...,0},{0,2,1,1,...,1},...{3,1,1,1,...,2}} So ...
35 views

### Finding Roots of Non-linear Systems: Rescaling polynomials

I'm trying to get all isolated finite equilibria of a moderate multi-dimensional non-linear system of equations. Particularly I have 9 independent variables and third order at most. It turns out that, ...
100 views

### Agglomerate output to Graph

I'm using the HierarchicalClustering package to cluster some data. So let's say I have this: ...
72 views

### Aborts and beeps without error warning

I have a piece of code that generates a figure, performing a calculation to generate each pixel. At a certain resolution it runs fine, but after a high enough resolution it fails. Mathematica beeps ...
38 views

### How to avoid joining MathieuCharacteristicA in a plot? [duplicate]

In the documentation As a function of the first argument, MathieuCharacteristicA is a piecewise continuous function So how to avoid joining different pieces of the function? For example, ...
28 views

### EvaluationMonitor is evaluating up to 3232 steps [on hold]

I have the following objective function which I want to minimize using simulated annealing. fourVertIsoHamilt[x11_, x12_, x13_, x14_, x21_, x22_, x23_, x24_, x31_, x32_, x33_, x34_, x41_, x42_, ...
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### Can I use what “headerlines” removes from a CSV as TableHeadings for the table I create from that File?

I am reading in some data from a CSV file that has a line which gives titles to each "column". Here is an example: ...
36 views

### Complex infinities in an Euler-Lagrange equation

I now wish to solve for $L(t)$ and $H(t)$ some ugly Lagrangian (in the code below) in configuration space, respectively the length and the height of a system. I tried running the code below, with the ...
160 views

### Problems extending NelderMeadMinimize into 2D

I've been playing around with Oleksandr's compiled Nelder-Mead Minimization function presented here: Shaving the last 50 ms off NMinimize First, I'll create some sample data. This creates a noisy ...
56 views

### Result of Integrate depends on order of integration although the domain is rectangular

The following: ...
846 views

### Linear programming with many variables and parameters

I am trying to reconstruct the answer that is given in this report. (page 153 in Appendix B; Section B.2.1). They are given variables, parameters, constraints, and the objective function to minimize. ...
564 views

### How to integrate a function over a 3D planar polygon?

I am trying to integrate a function over a planar polygon in 3D. In 2D, this is fairly straightforward, using either answer from this question (I use the second answer). If we use an equilateral ...
80 views

### Using J/Link with Wolfram Programming Cloud

Is it possible to use J/Link in a Wolfram Programming Cloud notebook? I need it to load and use 3rd-party .jars.
51 views

### Creating function with matrix argument

I am completely new to programming, so I apologize in advance for a stupid question. I want to program an algorithm for computing invariant factors of a finitely generated abelian group, so in ...
39 views

### Simplifying a symbolic product of rational powers

I'm trying to symbolically evaluate a lot of equations that can consist of up to 10 parameters. The form of these expressions is a product/quotient of rational powers of the mentioned parameters, ...
88 views

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