0
votes
1answer
9 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, ...
0
votes
1answer
21 views

How to read from /dev/random?

I am looking to read a few bytes from /dev/random on OS X and Linux. The simplest approach fails on both operating systems (see below). Why? What is a ...
6
votes
3answers
62 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 ...
0
votes
0answers
12 views

How do I turn my verbal argument into something formal in Real Analysis? [migrated]

So one of the exercises I am doing is to prove (or disprove) that 'Every compact set on a metric space is bounded'. Verbally, I can 'prove' this by simply stating: "If the every compact set on a ...
0
votes
1answer
21 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 ...
3
votes
2answers
42 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 ...
0
votes
0answers
45 views

Security of the Wolfram Programming Cloud?

We have a number of projects where we a contractually obligated to safeguard client data and intellectual property. Prior to using a tool or technology, we must provide documentation that shows how ...
1
vote
2answers
70 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 ...
0
votes
0answers
23 views

NDSolve PDE, not enough boundary condition?

The PDE that I want to solve is: $$ \frac{\partial f}{\partial t} + \frac{1}{m} \left( p_x \frac{\partial f}{\partial x} + p_y \frac{\partial f}{\partial y} + p_z \frac{\partial f}{\partial z} \right) ...
2
votes
1answer
49 views

About Compile Function

I have a function that take p as a parameter, p is a 2X3X3 list, ( a 2X3X3 list can like { {{2,3},{1,2.},{1,1.}}, {{2,3.},{1,2},{1,1}}, {{2,3},{1,2},{1,1}} } ) the function just as: ...
4
votes
2answers
109 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. ...
12
votes
2answers
453 views

Best practice of passing a large number of parameters to functions

I have a number of functions which all take a large number of parameters. I am wondering which is the best practice of passing these parameters to those functions. I could of course simply specify the ...
0
votes
1answer
34 views

How to use an output of a Solve function in further calculations? [on hold]

Following is the polynomial equation that gives me a single real root: ...
0
votes
0answers
37 views

Conditions under which a given function is less than zero [on hold]

I have a function say F(a,b,c,d,e) which I know can be positive or negative, depending on the values of the variables. Assume F(a,b,c,d,e) where variable "e" is the solution of G(a,b,e)=0 Is there ...
1
vote
4answers
73 views

Replacing more than one element from a Sublist

The following expression allows me to extract the value of x and y: ...
3
votes
2answers
68 views

Lookup in Inverse Symbolic Calculator+ from Mathematica

There is a useful feature in WolframAlpha that allows to find a possible closed form for approximate numeric values. It can be used, for example, to guess the value of an integral that Mathematica ...
0
votes
0answers
18 views

Simplify expression by restricting variable to be integer [on hold]

I have an expression $$\sin [2 n \pi]$$ here $n$ is an integer. How can I let mathematica know $n$ is an integer, so the expression is simplified into $0$?
0
votes
0answers
78 views

why is mathematica 10 much larger than 9 in disk space? [on hold]

I found that mathematica 10 requires 8.8GB disk space while version 9 only asks for 5.5GB. So what are the major differences? What kind of new features gives rise to the increase?
0
votes
0answers
31 views

What is taking so long in this simplification?

I killed this after 48 hours, it did not seem to be getting anywhere. In the best of all possible worlds it would spit out n!. If I put the summation in a function it does compute factorials ...
0
votes
2answers
42 views

Suppressing reduction in fraction box size in multi-level fractions [duplicate]

Mathematica display complex fractions like this, the second x look smaller, I want it look like this, how can I get it in Mathematica?
2
votes
1answer
56 views

Agglomerate output to Graph

I'm using the HierarchicalClustering package to cluster some data. So let's say I have this: ...
0
votes
0answers
32 views
4
votes
1answer
53 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.
0
votes
0answers
43 views

Finding Symmetries of Points on a Sphere

Currently, I am working on a project where I would like to find symmetries of points plotted on a sphere. One example would be to rotate the sphere 180 degrees about the x-axis and the picture would ...
5
votes
3answers
79 views

AssociationMap to query Dataset across levels?

Is there a way to operate on Dataset across levels to apply a function f to a key -> value pair in an Association as follows: ...
1
vote
1answer
55 views

notebooks not opening in mathematica 10

I`m a guest here, and thought I could just ask you guys. ...
1
vote
1answer
44 views

Constraint in a 2D plot with Legend

I have the following plot: ...
1
vote
1answer
41 views

Numerically Integrating to find a Maximum using NDSolve

I am trying to numerically find an equilibrium (maximum) of a function using its differential. The following is a simplified version. ...
1
vote
1answer
45 views

Some question on “Reduce”

Is this my mistake? I am trying to solve ...
0
votes
0answers
28 views

Set min and max ranges for axes in ParametricPlot

I'm having trouble with this one plot I'm trying to make. I'm using NDSolve on a system of differential equations and when I plot it with ParametricPlot, the scales or lengths of the graphs axes come ...
0
votes
0answers
35 views

Is it possible to build/simulate/extract data from a System Modeler model completely inside a notebook using the MathModelica language syntax?

See examples in: http://www.mathematica-journal.com/issue/v10i1/contents/MathModelicaPaper/MathModelicaPaper_2.html It seems to be ruled out by the statement (Chapter 2 intro): "The subset of the ...
0
votes
0answers
41 views

Approximate a function of four variables with a rational polynomial

I have a function that consists of four variables. Currently, I want to view it as function of one variable over the interval (0, 1) with the other three variables as parameters. I will plug values ...
0
votes
2answers
43 views

Defining a function from a list [on hold]

I have a list of 49 numbers, and I would like to define a function f such that f(n) is simply the nth number in the list. How can I do this?
3
votes
0answers
82 views

Mathematica 10 : Where is the Mathematica Book? [duplicate]

The question is simple. In Mathematica 9, there used to be "The Mathematica Book" integrated with the software in the help system. I can't find it anymore in version 10. Do you know if it is still ...
0
votes
0answers
61 views

FindMinimum slower in MMA10

I've recently updated one of my PCs (both have the exact same build) to Mathematica 10. After running the exact same notebook (which has two FindMinimum calls) on ...
1
vote
0answers
50 views

Why does Mathematica not go to specified order in series?

For some reason Mathematica will not evaluate this asymptotic series to the requested order. Inputting: ...
4
votes
2answers
62 views

Why can't I pass in a product of matrices in my modified matrixform? [duplicate]

In attempt to build a function that would work like MatrixForm but would wrap a matrix with brackets, I tried the following function: ...
1
vote
2answers
80 views

Line Breaks in AxesLabel or PlotLabel?

Searching got me peripherally related threads, but not exactly what I was looking for. I'm making some graphs which I want to use on exams. Sometimes, labels (specifically in AxesLabel and PlotLabel) ...
1
vote
1answer
80 views

Computational complexity of symbolic determinant

I'm using the Det function in Mathematica to compute the determinant of an $n\times n$ matrix $A$ with entries of the form $a+bt$ with $a,b$ integers and $t$ a variable, and I would like to know what ...
0
votes
1answer
38 views

Why my if statement does not work [on hold]

Thanks for your attention. I'm new to mathematica. I have the codes as below. But the If statement does not work. Anything wrong with my code? Thanks for help! Ben ...
1
vote
0answers
81 views

Classify - no memory available

I tried to use function Classify in version 10 on data sample with 15 parameters and around 1/4 million of records. I got this result: ...
0
votes
0answers
25 views

Problem with Flatten [on hold]

I am calculating the metric tensor and its components.I have a metric of 6 X 6 dimensional matrix that contains terms like 1/z^6 ...
0
votes
1answer
24 views

substitute definition when exponents are involved

Consider this simple case: ...
-2
votes
0answers
34 views

Random Packing and moving sphere [on hold]

http://www.youtube.com/watch?v=usu7OZiCvlg http://www.youtube.com/watch?v=oz8kT1Ii278 I want to simulate concrete. Does any can use matnematica to simulate filling a cubic zone with spheres like ...
1
vote
0answers
35 views

xCoba: evaluate tensor quantities, given an explicit metric

I am new to xAct packages and I'm having some problems to compute tensor quantities with xCoba. I defined a manifold and a metric. I computed All quantities of ...
0
votes
1answer
68 views

Contourplot of complex Roots

Suppose I have this equation: $$ z^2 + 3z + (x^2 + y^2) = 0 $$ I want the real and complex contour plot of $z(x,y)$. Analytically, the real/imaginary boundary is separated by condition $x^2 + y^2 ...
2
votes
0answers
33 views

Session logging of “\$Echo” and “\$Output” in Mathematica 10

I have difficulties with session logging and Mathematica 10. In previous versions, you could simply use AppendTo[$Echo, logfile] and ...
0
votes
3answers
66 views

How to draw a plane parallel to one of the coordinate planes? [on hold]

Sorry for the fact that I ask actually the same question on three different stackexchange sites (stackoverflow, mathematics and now here), but I need to find an answer to my problem as quickly as ...

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