# All Questions

48 views

### Request for clarification of Eigensystem::eivn message

What causes the problem of "two eigenvectors associated to one single multiplicity eigenvalue" that I am experiencing? After several transformations to simplify an unwieldy matrix, I end up with the ...
55 views

### ParametricPlot3D/2D won't work and leaves a blank space

I've been trying to evaluate this line ...
393 views

### Paste data into Mathematica with formatting

Select the following Mathematica code and paste it into a notebook. In Windows 7(Mathematica 8) the line breaks are not interpreted in the expression. In fact any data copipasted from stackexchange ...
123 views

### Concisely returning a position in an array with an index variable [on hold]

We have an array and an index in the array: exampleArray = Table[{a, b, "q"}, {a, 1, 10}, {b, 1, 10}]; arrayIndex = {5, 4}; Very simply, we can return the value ...
261 views

### How to build a 3D graph from a 3D matrix?

Following this and that question and the corresponding answers, Mathematica can build 2D graph from 2D matrices. Question How to make the corresponding 3D graphs from 3D cubes? Attempt ...
46 views

### A problem about sorting final result

Three days ago, I asked a question about B-Spline Basis fuction here @Michael E2 given a solution to make the order of interval looks normal The easiest way would be to sort it afterwards: ...
69 views

### Mapping a function of the form matrix[[row,column1;;column2]] over a list

I want to create a list of lists of values by mapping values[[row, col1;;col2]] over a list like {{r1,c1,c2},{r2,c2,c3},... } to ...
43 views

### Plot is not accurate [duplicate]

I defined a matrix and use it to transform a square defined by four points. (In[85]) It seems the transformation keeps the length of the square. (In[91]) Now I plot the original square, the axis of ...
38 views

### Getting a blank plot when plotting two functions with Plot3D [on hold]

I want a 3D plot of two functions of two variables, but I am not getting any result. Please help me out. The program follows: ...
32 views

### replace an interval of values [duplicate]

I want to replace values in an interval [a,b] by 0 in a list of values. Example: {{.5,.2,.49,1,1},{.49,.5,.495,1}} I want to get: ...
111 views

### Can a Mathematica Application be inside another Application?

The file structure of a simple MMA Application can have the form: MyApplication MyApplication.m SomeAuxiliarPack.m Kernel init.m Where ...
67 views

### Equivalent of RadialOutside for Graph VertexLabels

I'm creating a circular graph and want the labels to be placed on the outside of the vertices in a circular manner on the outside of the graph. I've been playing around with the ...
11 views

### LibraryFunctionLoad not recognizing datatype

I am trying to use LibraryFunctionLoad with a function that relies on a derived type that is defined within the library. I've loaded the library prior to calling ...
162 views

### Not able to get a solution to a Lagrange Multiplier Equation

I assigned several constrained optimization problems to my calc IV students to solve with Mathematica, but this one is being stubborn. The function to optimize is: f(x,y,z) = y Exp[x-z] with the ...
61 views

### DateListPlot with multiple data sets and incongruous timelines?

I am using Mathematica to analyze some sales data for my company. (A copy of the available data is here.) We are trying to analyze the sales trends for each month by item. DateListPlot works well ...
93 views

### Collapsing summation

I am trying to write a command to collapse the sum of terms into an expression with summation. Something like ...
76 views

### Finding relevant parts in XML document

My qyestion is about a XML document and finding parts of strings. test = Import["C:\\Users\\filename.xml", "XMLObject"] This gives the following output: ...
441 views

### How can I remove B -> A from a list if A -> B is in the list?

I have a list of transformations like this: list = {"A" -> "B", "B" -> "A", "C" -> "D"} As this is used to plot an undirected graph with ...
60 views

### Association and rudimentary object-oriented programming

Doesn't Association provide us rudimentary object oriented programming via constructs like ...
63 views

### Detect Messages within an expression without losing the return value?

I know that Check[expr,failexpr] is a mechanism to catch messages. The problem with it is that if a message is generated within ...
212 views

### What is the best way to flatten a linked list with lists as values?

By following the advice on this site I have ended up with a linked list like the following: acc = {{1, 2}, {{2, 3}, {{3, 4}, {{4, 5}, {{5, 6}, {}}}}}}; This was ...
44 views

### defining Associated Stirling numbers of the Second Kind

First, I'm new to Mathematica. Spent my undergraduate programming with Maple and my computer crashed and I lost it. Fortunately, my university offers free Mathematica downloads to students, so here ...
112 views

### Unable to compile to C

I used to be able to compile to C without problems, but from one day to the next, when I try to compile something, e.g. ...
66 views

### Matrix elements scope definition

Alright, I'm very new to Mathematica and I have yet to learn a lot so please bear with me (sorry if this is a duplicate!): I want to create an $n\times n$ matrix $C$ with elements $c_{i,j}$ with \$i,j ...
79 views

Code: ...
266 views

### Connect neighbouring points as list of segments in 2 D

Context I am interested in connecting neighboring points in 2/3D as list of segments. I am guessing this is something within the reach of graph theory, which is well implemented in mathematica. ...
49 views

244 views

### Can I generate a “piecewise” list from a list in a fast and elegant way?

Suppose we have a number list a: n = 1000000; a = RandomReal[{0, 1}, {n}]; We want to generate a list ...
24 views

### Disable locator-removal in LocatorPane

is there a way to DISABLE the ability to remove points with ALT-click (APPLE-click) from a locator pane? I'm writing a code that allows users to manually label objects in an image by connecting two ...
4k views

### How to create animated snowfall?

Well, the title is self-explanatory. What sorts of snowfall can we generate using Mathematica? There are two options I suggest to consider: 1) Continuous GIF animations with smallest possible number ...
114 views

### Cases do not return all expected result

I have the following line code: Cases[g[h, r, t, b, m], x_[__, y_, __] -> y, {0, -1}] I am expecting the results to be ...
133 views

### Graph showing valid English words obtained by insertion of single characters

I'd like the most efficient Mathematica code for making a formal tree graph whose nodes are valid English word strings (in DictionaryLookup[ ]) and directed links represent the relation 'insertion of ...