0
votes
1answer
95 views

Z-Transforms and Floor Functions

When I take the $Z$-Transform of the Floor function: ZTransform[ Floor[x], x, z] I get ...
0
votes
1answer
151 views

iterative programming

i have 3 equations with 3 variables and two constants(to be substituted repeatedly). the value of the variables we got by applying nsolve on the system of 3 equations assuming some initial value for ...
6
votes
0answers
145 views

Automatic replacing of [ with []

I tried to modify the KeyEventTranslations.tr file in order to always place a closed bracket instead of an open bracket once I press ...
1
vote
1answer
151 views

RegionPlot of a Double integration [closed]

Hey guys I have a problem where I want to sketch the region of integration: Integrate[x Cos[y^2], {x, 0, 3}, {y, x^2, 9}] I know I have to use ...
5
votes
4answers
311 views
11
votes
2answers
308 views

Rotational Averaging of Image Periodograms (FFTS)

I'm writing a code to do rotational averages of image FFT's. I have a working version but it is pretty slow. Wondering if anyone has any thoughts on a way to do this more efficiently. Data looks ...
5
votes
2answers
378 views

Understanding Transpose

It is very likely that it is my lack of math skills that is showing up here. However, I think Transpose is such an important function that I need to master it. So I ...
0
votes
0answers
78 views

Solving an exponential inequality with parameters

Can I use Mathematica for solving the inequality given below? b^(x/2 - 3/2) - b^(ax) - 2c > 0 where b, a, c are the parameters. I want to find out for what ...
3
votes
0answers
95 views

Derivative of generating function (Example from documentation)

In the documentation for GeneratingFunction, the following example is given under Examples -> Properties & Relations -> Derivative: ...
0
votes
1answer
97 views

How can I fix my code so NIntegrate doesn't produce error message?

I get this error when trying to integrate a seemingly simple expression: ...
5
votes
3answers
173 views

Creating centered inline cell in text cell

The cell corresponds to the textual form ...
3
votes
1answer
66 views

How does GroupActionBase affect the order of elements in a group?

Related (math.SE): How does the base of a group determine the “sort” of the elements in the group The help page for GroupActionBase says: A base of a group ...
4
votes
1answer
237 views

Partitioning an image based on features

I have an image that has various characters hand drawn in it, like numbers and letters. I'm trying to partition each character into it's own image so I can run it through ...
3
votes
0answers
101 views

Getting Arg[z] to go from $0$ to $2\pi$

I'm defining branch cut functions, and I'm using $arg(z)$ as a building block. So I just spent an hour at the whiteboard assuming that $arg(z)$ goes from $0$ to $2\pi$, and then I implement the code, ...
1
vote
2answers
110 views

Select record when third column matches certain criterion

I've a table with 3 columns. The table looks like this: ...
3
votes
1answer
195 views

In LineLegend, how do I force the legend entries to appear in a single column?

I want to create a single column LineLegend with at least 12 different entries. Suppose that I define lists colors and ...
2
votes
1answer
210 views

Dynamically Updating Function

I use Mathematica 8 and am working with DynamicModule. I'm trying to enter a function in an InputField then later apply it to two values entered in subsequent Input Fields. The function just does not ...
6
votes
1answer
388 views

Export to PDF on OS X, font missing on Windows

Here is another problem with Mathematica plots and PDF. I have Mathematica 9.0.1 on Mac OS X. I want to export my plots to PDF to include them in a LaTeX document. If I export the plot with the ...
1
vote
1answer
115 views

Operator operation

There are two basic operators r={x,y,z} and p=-I*h*{D[#,x] , D[#,y], D[#,z]} &. The angular momentum operator is defined as ...
2
votes
0answers
57 views

Can BreadthFirstScan be modified?

I would like to obtain a "slick" implementation of A*-search algorithm on Graph objects, using the built-in BreadthFirstScan (if that is possible at all). I noticed that BreadthFirstScan is static in ...
3
votes
0answers
117 views

What can I do to improve the performance of my calculations?

I'm trying to express a simple probability problem in Mathematica, but am having trouble getting my calculations to execute at a reasonable speed. I have an object whose unknown location is modeled ...
1
vote
2answers
71 views

How to define a function $f(x)$ such that $f(1.5)=1.5$, $f(1.)=1$, $f(0.)=0$, etc.?

How to define a function $f(x)$ such that $f(1.5)=1.5$, $f(1.)=1$, $f(0.)=0$, etc.? Namely, if $x$ is an integer with a decimal point, $f(x)$ returns the integer only, otherwise returns $x$. This ...
0
votes
1answer
237 views

I don't understand ListCorrelate! [closed]

I want to solve a PDE equation (like Schrodinger equation) using finite difference in Mathematica. I don't understand what this code does! ...
2
votes
1answer
126 views

Convert frequency counts to long notation in Mathematica

I have a series of frequencies of values, e.g. 5 times 1, 10 times 2 and 5 times 3, as in list={{1,5},{2,10},{3,5}} and I would like to convert this to long ...
3
votes
1answer
121 views

Is it possible to get AltGr key to work in Math.exe?

For some reason when you run Math.exe form windows command line, Mathematica disables the AltGr key. This is a bit annoying since my keyboard locale has the keys [, ], {, }, @, $, \, | located under ...
0
votes
2answers
131 views

How to partition three years of data into daily samples

I'm trying to find mean of temperature data list. The temperature data list has 3 hours steps which means I have 365*8=2920 temperature measurements per year. My data are temperatures of 13 years. ...
0
votes
1answer
243 views

predator prey model with prey refuge

I want to plot the phase diagram of prey predator versus prey refuge to see how the prey refuge influences the population of prey and predator.And this is the system $x'=\alpha ...
1
vote
1answer
68 views

Mathematica quits calculation automatically

I have this little program that is adopted from a Wolfram demonstrations project (link here: http://demonstrations.wolfram.com/PercolationOnASquareGrid/). I want to see what happen if I increase the ...
-1
votes
1answer
139 views

Mathematica Compute Time Is Extremely Long (Integrate simple function with parameter scan)

I was wondering if you can help. I have a set of equations I need to solve for a list of parameters; entering each parameter value and solving anew each time is simply not economical. I found a way ...
3
votes
1answer
94 views

Why does Mathematica list the variables in a double integral backwards? [closed]

I am an advanced novice Mathematica user and have done a fair amount of single-variable calculus things with it. This semester I am using Mathematica for multi-variate calculus and when I tried to ...
1
vote
3answers
167 views

Plotting a frequency function

I have a list of numbers and I want to plot the fraction of numbers >= k against k which will naturally be a decreasing curve. How do I do that?
6
votes
1answer
276 views

Coloring a honeycomb structure

I am trying to generate a honeycomb structure. With the help of this MMA.SE question & this website, I got ...
1
vote
1answer
124 views

Help to solve the equation with RungeKutta method [closed]

I need to solve this equation. v'[t] + v[t] == 1/(1 + Exp[-v[t]]) I tried to solve it using RungeKutta method described in Wolfram ...
2
votes
0answers
95 views

Setting an initial value for ListAnimate?

ListAnimate is fairly similar to Manipulate, but while Manipulate has a simple way to request an initial value for the manipulation parameter, I haven't found a way to tell ListAnimate to start with a ...
3
votes
1answer
132 views

How can I get precise frame rates in dynamic?

I've been the Spritz sdk in my ios apps, and I love it. For funsies I wanted to see how much less code a mathematica version would take! Using dynamic I get a nice result, shown below in code. ...
0
votes
2answers
292 views

Are solid spherical harmonics implemented in Mathematica?

In certain applications, solid spherical harmonics can be very useful. They are essentially the usual, 'surface' spherical harmonics, with the appropriate power of the radius inserted: ...
3
votes
2answers
443 views

Package for representation of groups (group theory)

I wanted to know if there is a package which allows to compute representations of a group like the definition representation, adjoint and so on (for example the Pauli matrix for $SU(2)$ if I specify ...
0
votes
1answer
82 views

Creating If statements programmatically [duplicate]

I want to write an algorithm that returns a sequence of numbers, starting from a specified point but stopping once a criterion has been reached. For example ...
1
vote
0answers
38 views

How can I select two lists from a list of lists so that I receive the system of equations has only rational solutions?

I want to make a sytem of equations has the form $$\begin{cases} a_1x^2+b_1y^2 + c_1xy+d_1x + e_1y+3=0,\\ a_2x^2+b_2y^2 + c_2xy+d_2x + e_2y+3=0. \end{cases}$$ so that the given system of equations has ...
1
vote
1answer
70 views

Solve never terminates with simultaneous equation set

I have the following set of simultaneous equations that I want to solve symbolically. The two unknowns are $a$ and $d$. $a=\frac{c*(d/10)}{1 + (f/130) + (d/50)} - \frac{a}{1 + (a/100) + (d/100) + ...
0
votes
0answers
81 views

Solving a single equation with multiple parameters

If I wanted to solve equations like Cos[x]^2 = A Cos[Bx + C] + D what function should I use? The Solve function seems to only solve for as many variables as there are equations. Please note that my ...
0
votes
0answers
30 views

JacobiCN inaccuracy

For my calculations I need JacobiCN[s,k] for s near 0 from the left and k near 1 from the ...
2
votes
1answer
161 views

Showing ListLogPlot and redrawing FrameTicks

I want to combine two ListLogPlot plots. For example ...
1
vote
1answer
101 views

Connecting to a SQL Server Instance

What is the syntax for connecting to a specific instance of a sql server database? Here's my code: ...
0
votes
1answer
218 views

How do I keep my Animate running at high resolution?

I'm building an Animate where I have a 3D plot with some of its parameters changing: ...
-1
votes
1answer
81 views

MANIpulate. How to put labels and fit 24 vslides in a row? [closed]

How could I fit 24 vertical slides in a row?, in the up and How to add any reference like 0 and 8 ? and how to add 2 options boxes in the right under the vslides (or to the right of vlides??? What ...
0
votes
1answer
37 views

Generate array of every $n^{th}$ integer between two bounds [closed]

I want to generate the series {1930, 1934, 1938, ..., 2014} with Mathematica. I found that I can use Sum[2014-m*4, {m, 20}] to ...
7
votes
1answer
136 views

Equivalence under common permutations

I have lists which consists of sublists of equal length. The outer list is regarded as a multiset (that is, permutations of the sublists don't matter, but repetitions do), but the order in the ...
2
votes
1answer
1k views

Running a shell script within Mathematica

The title pretty much explains it and I have not found something similar already posted. Perhaps I am not searching for the correct title or maybe this is something very basic, but I would appreciate ...
1
vote
1answer
114 views

Mathematica does not respect tensor order?

I'm trying to verify an identity involving symmetric traceless tensors over the reals. What I tried was: ...

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