3
votes
2answers
165 views

Stopping a head from evaluating more than once

While attempting to answer my own question, Is there a way to "hold" prefix / infix / postfix notation?, I came across the need to evaluate a recursive function only one level deep. For ...
3
votes
1answer
120 views

How to transform an equation so that the coefficient of a certain term becomes 1

Say I have an equation like A + 5 B + 10 C == 0 and I want to have Mathematica write this as (A/5) + B + 2 C == 0 i.e., I ...
1
vote
1answer
196 views

Splitting dates into groups in half year steps

list = DayRange[{1999, 1, 1}, {2014, 2, 6}] I want to split this list into sublists one and a half year long, moving a half year forward every time. That would ...
3
votes
1answer
200 views

Writing results directly to file

I am trying to find all simple paths in a large directed graph (542 vertex, density ~ 5%) between two nodes. For this purpose, I use the algorithm from this thread. Unfortunately, my computer is ...
1
vote
2answers
174 views

Is there a way to “hold” prefix / infix / postfix notation?

Is it possible to preserve a specific style of notation in $Mathematica$ output? foo // bar (* bar[foo] *) Hold[foo // bar] (* bar[foo] *) I'm writing some code ...
1
vote
1answer
84 views

How to get all permutation of k-partition

If I want to get the list of k-partition, and the rule are below: here are k partitions all elements of partition are in the range of 1 to 30. the total of ...
6
votes
1answer
286 views

Young Tableaux Miscellanea

I have a problem which is mostly neatly described by using Young Tableaux. Mathematica seems to have these Tableaux built in, except that the Tableaux function is ...
6
votes
2answers
747 views

StreamPlot for Bifurcation Diagram

When we do a StreamPlot, I want to show the bifurcation when $a = 0$ transitions to $a >0$, but do not see a better way to do this than the following. ...
0
votes
3answers
157 views

Implementing nested subtotals

Inserting a nested subtotal in a spreadsheet is a facility that Excel performs very well. But if a subset of this facility can be implemented in MMA for a table which needs it the hassle of its ...
1
vote
0answers
169 views

Extract coefficients of differential form in package RGTC

I am using the Package RGTC to do some calculations in Supergravity. It allows to define differential forms after specifying a co-frame. I am working in with the 10d coordinates ...
5
votes
1answer
109 views

Why does a heavy background slow LocatorPane from updating, even if only the locators are Dynamic?

I'm having some trouble getting a dynamic plot to operate efficiently, and I think I've tracked down at least part of the problem to some pretty weird behaviour on the part of ...
1
vote
1answer
344 views

Import invocation fails with Get::noopen : Cannot open JLink error

The following function call fails when I invoke it in a fresh Mathematica session: ...
1
vote
2answers
217 views

MathLink Graphical Output (Plots) to File

In a custom Mathematica frontend based on MathLink I try to make use of plots produced in Notebooks. The idea is to write them to files whenever they get produced. According to C-code snippets I ...
0
votes
1answer
74 views

Using Derivative with list in curly brackets

I'd like to make a formula for a sum containing Derivative where the number of arguments in the latter depends on an input parameter n. Also involved is a list ...
13
votes
2answers
139 views

Why the Block command does not forget the $ContextPath variable

I do not understand this behavior: ...
3
votes
2answers
375 views

Copy and paste behaviour with Subscript

I tend to use a lot of subscripts in my code, and I am aware that copy and paste of subscripts from Mathematica to MathematicaSE (or any text editor, for that matter) is screwy in the sense that $a_b$ ...
1
vote
1answer
104 views

How to define an n-variate empirical distribution function probability for any n?

I'm using Mathematica 9.0 to calculate the probability according to the empirical distribution function (EDF) of some sample data. Afterwords this is included in a maximization stage so I define this ...
0
votes
1answer
136 views

Why do InputFields not respond in Manipulate utilizing FindGeometricTransform?

In the following code changing the InputField does not result in observing changes in a result from FindGeometricTransform, but ...
16
votes
2answers
257 views

Third argument of Compile

In his last comment on this answer, halirutan shows an example in which the third argument of Compile does not have any effect. The example is as follows. ...
0
votes
0answers
72 views

coding simple structures, potential problems (multithreading) and how to solve them

This post contains two parts. In the first part I will explain what I am trying to do. In the second part I will explain what I fear. My questions are about these fears. Are they justified and if yes ...
1
vote
1answer
115 views

How to assign Subscript[C, i] to a Sum?

What I want to show is: Plot3D[ Sum[1000*Subscript[C, i]^2/(1000*Subscript[C, i] - 600)^r, {i, 1, k}], {k, 1, 30}, {r, 0.1, 1.5}] And, I want the list of ...
1
vote
1answer
201 views

Find missing values in time series and fill them with Na

I have this list list = {{1, 3}, {3, 7}}; representing a time series from t = 1 to t = 4. How would I go about filling the missing values so that my list looks ...
3
votes
1answer
616 views

Why is Solve returning an empty list?

I evaluate ...
9
votes
2answers
309 views

How to see which arguments are passed into a function

It is often that one wonders which arguments are evaluated before being passed into a function. I would like to know if it is possible to see which argumets are being passed into a function without ...
1
vote
2answers
94 views

Apply a function to each element of a list and sum it

I have a list {-1.8, 1.44, 0.2736, -1.72514, 1.17612} where each element stands for a value of x. e.g. $x1 = -1.8$, $x2 = 1.44$ and so on. How can I find the ...
3
votes
0answers
158 views

Non-linear integral equation

I'm trying to solve with Mathematica an integral equation. I found this excellent answer (How to solve a non-linear integral equation?) solving with a collocation method a problem which can be ...
1
vote
1answer
36 views

How to assign a list of subsript?

I want to assign Subscript[C,i] by mapping a specific list. For example, the list is {1,2,3,4}, and I want to assign 1 to C1, 2 to C2, 3 to C3 and 4 to C4. How should I do? Many thanks:)
0
votes
0answers
40 views

Green functions for recurrence equations

Is it possible to solve recurrence equasions in Mathematica with the use of Green's functions and get a solution as a series?
26
votes
1answer
451 views

Are greek symbols causing different evaluation?

I've updated today to Mathematica 9.0.1.0 from version 8 and found something that absolutely confuses me. Let us define a piecewise function: ...
0
votes
1answer
80 views

Getting error FullSimplify::infd: … simplified to ComplexInfinity

I tried to run the following code: ...
1
vote
1answer
114 views

Equation Simplification in Mathematica

I wonder if the following equation could be further simplified by Mathematica. There are $22$ Integrals involved and many of them are in the range $y_l$ and $y_u$. I would guess that at least those ...
13
votes
4answers
324 views

Replacing parts of a held expression with held parts of another expression

I'm applying the Trott-Strzebonski technique in order to replace inside a held expression. ...
2
votes
1answer
263 views

Finding the optimal teams ranking based on the table of match results

My original question was this: So my task is to score all the possible rankings of the 14 SEC football teams and find the best one, using who won in head-to-head games as the sole criterion ...
13
votes
4answers
527 views

How to make a function with its own options as well as passing options to other functions [duplicate]

I have a function with many of its own options, but I would also like to pass options to subfunctions using the FilterRules function. Here's a simple example: ...
3
votes
1answer
273 views

Mathematica 9, Mavericks, Java

I've been trying to get a clear story regarding the interaction of these three components before upgrading my system from Lion to Mavericks --- I can't afford a Mathematica disaster. What I think is ...
1
vote
1answer
76 views

Using imported data in further calculations

I have quite a lot of data in an Excel file, which I have to use in further calculations. The transformation should map a data point with thre coordinates into a two coordinate result. Example: ...
3
votes
1answer
303 views

Draw grid with points

How would I draw a grid with dots on specified intersections? The image below shows the basic idea: If I wanted to label the grid lines with index numbers or letters, how would I do that?
0
votes
0answers
46 views

Block, With, Module, can anyone help me understand the distinction? [duplicate]

I've been working heavily with Block[] for months in my research so I've read the documentation for the seemingly similar commands With[], Block[], and Module[]. Personally, I've had by far the ...
0
votes
0answers
78 views

Solve gives solution with ComplexInfinity -> number

I am trying to solve a cumbersome equation using ...
1
vote
3answers
604 views

How to expand the size of the matrix automatically?

I have a matrix in 2x2 a ={{x, y}, {z, u}} I want to expand this matrix 3x3 b ={{x, y, y}, {z, u, x}, {z, x, u}} 4x4 ...
1
vote
1answer
44 views

Cell seems to be evaluating in exponential time even though it shouldn't

I am trying to implement Newton's method for a given function f[x] and a starting x-value xval. The code should print out each new x-value as it approaches one of the zeroes of the functions. g[x] is ...
2
votes
4answers
632 views

How to calculate the position of a figure in an image?

My question is about recognising soccer players in the pitch. Thanks to Bill S who wrote an excellent script to recognise parts of the players. I found this issue after testing his solution. I will ...
4
votes
2answers
73 views

With command does not behave as expected according to its Attributes

The attributes of the With command are HoldAll which means it should not evaluate its arguments before its starts its business. ...
3
votes
1answer
192 views

Clustering of 2D map, based on similarity in spectra

I have experimental 2D-spectroscopy data, in a format similar to this: ...
5
votes
3answers
344 views

Series coefficients for an infinite sum?

I'm working through Carl Bender's Mathematical Physics lectures on YouTube (which are great fun), and I'd like Mathematica's help solving terms in the perturbation series. It would be convenient if ...
0
votes
1answer
129 views

2 Equations continuous at a point

I want to get continuous point between two equations. My equations are: ...
0
votes
1answer
66 views

How to find all subsets which the total of elements is the same?

I want to find all subsets which the total of elements is the same. For example, Subsets[Range[30], {5}] means all 5-element subsets and the range of each element ...
6
votes
1answer
381 views

Parallel optimization of Markov Chain Monte Carlo

I'm trying to reduce the computation time of a MCMC simulation. Essentially I have a set of particles performing a random walk in a periodic random potential. The particles are independent and every ...
1
vote
2answers
153 views

Problems with importing a .txt file

I have some problems with importing a .txt file as a table. This is the file. I tried importing it with data = Import["data.txt", "Data"] I want to access ...
2
votes
1answer
200 views

Internal Shooting Method of NDSolve in combination with NDSolve`Reinitialize?

To explain my problem, I am trying to extend the BVP problem example from the help that illustrates how to use the shooting method of NDSolve: ...

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