# All Questions

95 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: ...
172 views

### Creating centered inline cell in text cell

The cell corresponds to the textual form ...
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 ...
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 ...
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, ...
109 views

### Select record when third column matches certain criterion

I've a table with 3 columns. The table looks like this: ...
192 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 ...
209 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 ...
382 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 ...
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 ...
56 views

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 ...
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 ...
70 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 ...
235 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! ...
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 ...
120 views

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 ...
136 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 ...
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 ...
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?
275 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 ...
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 ...
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 ...
130 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. ...
285 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: ...
438 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 ...
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 ...
37 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 ...
70 views

I have the following set of simultaneous equations that I want to solve symbolically. The two unknowns are $a$ and $d$. $a=\frac{c*(d/10)}{1 + (f/130) + (d/50)} - \frac{a}{1 + (a/100) + (d/100) + ... 0answers 78 views ### Solving a single equation with multiple parameters If I wanted to solve equations like Cos[x]^2 = A Cos[Bx + C] + D what function should I use? The Solve function seems to only solve for as many variables as there are equations. Please note that my ... 0answers 30 views ### JacobiCN inaccuracy For my calculations I need JacobiCN[s,k] for s near 0 from the left and k near 1 from the ... 1answer 158 views ### Showing ListLogPlot and redrawing FrameTicks I want to combine two ListLogPlot plots. For example ... 1answer 100 views ### Connecting to a SQL Server Instance What is the syntax for connecting to a specific instance of a sql server database? Here's my code: ... 1answer 215 views ### How do I keep my Animate running at high resolution? I'm building an Animate where I have a 3D plot with some of its parameters changing: ... 1answer 81 views ### MANIpulate. How to put labels and fit 24 vslides in a row? [closed] How could I fit 24 vertical slides in a row?, in the up and How to add any reference like 0 and 8 ? and how to add 2 options boxes in the right under the vslides (or to the right of vlides??? What ... 1answer 37 views ### Generate array of every$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 ...
132 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 ...
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 ...
113 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: ...
122 views

### Interpolation impossible for ListPlot with Missing?

I have a list of data to plot. I would like to plot them with lines but delete some data before plotting and leave the lines disconnected where data is deleted. For example, ...
105 views

### Name scope confusion

Sorry for the too ambiguous title. First consider a following code snippet. ...
133 views

### Country borders and grids with CountryData plot?

I am coloring several countries in the manner of the following: ...
5k views

I'm new to Mathematica, I've been learning by myself, and, being a Java developer for some time, it makes it hard to adapt. I've tried to solve a Reddit challenge, and I came up with this solution: ...
213 views

### marking the points of x-intercept on a plot

OK, I have a nice plot of some oscillating motion. I can read some stuff off the graph, but I thought it would be cool to show a dot where the curve hits the x-axis and a little label showing the ...
98 views

### How do assign an interval of values to a variable in order to use them in a function?

From my code (below) I have K1 and K2 set to zero in order to test this numerical method. However, K1 is on an interval from 0 to 32, and K2 is on an interval from 0 to 8. I would like to know if ...
70 views

### Mathematica: Extract the piece that contains x=0 from within a piecewise function

In mathematica, I have a piecewise function similar to: Piecewise[{ {x^2 + 2*x - 4, 0 <= x <= 1/4}, {0, true} }] I don't ...