# All Questions

68 views

### Restricting a plotted expression to reals in a Manipuate

I have an expression from which I'm trying to create a plot that I can manipulate. The expression contains Abs, and I only want to have it evaluated for reals. What ...
1k views

### Discrete FFT of non-periodic signal excited by short pulse

Say I have a signal F(t) which represents a excitation by a pulse (so it is not periodic and declining to zero amplitude). According to this answer, for instance, ...
498 views

### Implicit differentiation to find the slope of the tangent line to the graph at the indicated point [duplicate]

I used ContourPlot to plot the graph of x Sin[Pi y] - y Cos[Pi x] == 1 with the following input: ...
368 views

### Creating ordered triplets from an Excel sheet

I have an Excel sheet of the form: " " a b c 1 R S T 2 U V W 3 X Y Z Where every entry is a number (except the blank quotes, ...
253 views

### Export to mat file does not work

I use this command from the Mathematica documentation center Export["1.mat", {"t" -> {{1,2,3}},"u" -> {{4,5,6}}}, "LabeledData"] to save data as mat file ...
99 views

### NMaxmize with a list of variables

I want to use NMaximize to find the maximum value of a function with multiple variables. The problem is I would like to set this up so the number of variables is only decided when the function sees ...
55 views

### DeleteCases and Inequalities [duplicate]

I would like to remove cases from a list according to an inequality rule - e.g. remove all values less than x. I can do the following but this seems very clumsy: ...
178 views

### Crash with subsetting TemporalData

The first line gets a single sample path for an M/M/1 queue for time between 0 and 100. No problem, I can plot it, etc. ...
299 views

### Why is ReplaceAll behaving like this?

I'm learning to use the ReplaceAll function and I found the behavior of which is quite confusing. For Sqrt[f[x, y]] /. f[___] -> u Mathematica returns ...
592 views

### Dropping Higher Order Terms in symbolic evaluation

I have a series of symbolic manipulations (along with some coefficients). As a sample, here is one of the intermediate forms ...
349 views

### Using non-trivial objects in RLink

I would like to use RLink to access igraph, which has an R interface. I do not know R; my motivation for learning it is to be able to access igraph easily. I installed igraph using ...
105 views

187 views

### Match and replace subexpression

I would like to replace the expresion $(n1-1)$ to $z1$ in following: In[1] := 2*n1*p[n1-1,n2] Out[1] := 2*(z1+1)*p[z1,n2] I have tried ...
373 views

### How to prevent errors in Manipulate with ListPlot when a result is an empty list?

I am trying to plot two lists, where one is the reference list, and the other is only used to select and highlight the first list. Basically, I want to use the selection list ...
270 views

### Is there any way to force Mathematica to collect a symbol in a polynomial?

Let's say that I have a polynomial like this: a + b + c Is there any way that I can get Mathematica to transform it to: ...
352 views

### How can I connect database(MSSQL Server) with Mathematica?

Newly I started working with database(MSSQL Server 2012). by google help, I created Table name as EmployeesList and also ...
824 views

### How can I find the Fourier series from discrete data?

I would like to define the function with Fourier series when I just have discrette data. (I don't have a specific function). I can draw the graph using the data, but I don't have a idea how can I get ...
253 views

### Unexpected behavior of rule matching a pattern

I am a beginner exploring the world of Mathematica. I expected the following code T[6, 5, 4, 1, 2, 3] /. {T[a___, 1, b___] -> Length[List[b]]} should return ...
101 views

### Getting value of clock [duplicate]

I have the following code: a = Dynamic[Floor[Clock[2]]] (*So this basically alternates between 0 and 1*) If[a==1, Print["true"]] But this doesn't work, it ...
140 views

### How to create a button that colors a selected piece of text in a cell?

I use Mathematica 9.0.1 and I want change the color of a selection in a text cell using a button. But when I use this code it changes the color of the entire cell. ...
241 views

### Background color of Code cell lost when convert a notebook file to pdf

Well, I have a notebook with the built-in stylesheet Preprint, which I'd like to convert it to pdf. Everything works well except for the code cells(I use the shortcut key alt+8 to create cells of code ...
2k views

### Removing zero values from ordered pairs

I have some processed data, which are basically a collection of ordered pairs in the form: {{x1, y1}, {x2, y2}, ..., {xn, yn}} Ordered pairs which have either a ...
149 views

### problem with Importing multiple files

I need to import about 100000 "dat" files to my progrom. I want to do this using the last answer to this question: Importing multiple files using a for-loop I know that I should define a list of all ...
341 views

### Integral evaluation taking too long [closed]

When I try to evaluate the following integral, it runs for a much longer time than I think is should without producing a result. What might be the problem? Can anybody please point it out? ...
575 views

### How can I draw a Cuboid given its center and its dimensions? [duplicate]

I want to draw a Cuboid accroding to the coordinates of its geometric center and its dimensions, rather than its diagnoal coordiantes. And How can I draw a triangular prism?
303 views

### Efficiently filling area with disks located at certain points

Starting from a set of points, I want to fill an area using disks. Each disk's center should be one of the points and the disks should not overlap. I've managed to write a function that, given a list ...
239 views

### How to migrate or export projects with Workbench

Imagine the following scenario: user A is developing a project with documentation in workbench. She wants to give her (unfinished) work to user B , so that user B can continue work on the project and ...
255 views

### Reduce on equations involving integrals

Here's part of problem from a college physics text: A time-dependent force F = (8.00 i - 4.00 t j) N (where t is in seconds) is applied to a 2.00-kg object initially at rest. (a) At what time ...
546 views

### Defining a new Function using RegionPlot

I'm trying to make images like this: to illustrate 2D integrals to a calculus class. I used the code ...
847 views

### Using ChemicalData to make molecule graphics

I would like to take the acetone $((CH_3)_2CO)$ and chloroform $(HCl_3)$ molecules that Mathematica's chemical data provides, and plot them together. I want to show how chloroform can hydrogen bond ...
1k views

### Sequence of data in 3D, joining the points

Let me just first say I am not actually trying to find a function for these set of data. All I am doing is joining the points to make a line. Basically let's say I have some data, which I cleverly ...
37 views

### Symbolic Calculations with formal matrices [duplicate]

I want to make calculations with matrices in the form (for lovers of statistical mechanics, is just the first step replica symmetry breaking) ...
172 views

### Manipulate - Flickering graphics

I am new to mathematica and was experimenting with NDSolve and doing a simple demonstration of orbital motion and Newtons laws. I put together the following code which all seems to work except the ...
169 views

### Iterating Reads From a Text File and Writing the Results of Operation

I have a very large text (TSV) file. I am able to now read single line, thanks to StackExchange. I am able to read a part of that line using the part operator. I want to iterate through the whole ...
718 views

### NDSolve: Normalizing at every step

Suppose I have an transport equation with an initial conditions: ...
136 views

### Functions, Options and Symbols

In the normal Mathematica language, where no built-in symbols are redefined and no evil things happen, is it a valid assumptions, that no function symbol (Plot, ...
408 views

### Replace operators

/. can be used to replace variables but how can one replace operators. For example in a * b, ...
395 views

### Looking for a package regarding Schur Polynomials and Kostka numbers

I'm currently looking for any Mathematica package that involves Schur polynomials and/or Kostka numbers. More generally, I'd be happy with anything that expands on symmetric polynomials in general. ...
28 views

### What is the precision of this number? [duplicate]

In a matrix evaluation, I got the following number. 2.8330574963868513 I understand that the number after  shows the precision of the output number. But this ...
469 views

### BC for transport equation using NDSolve

First I can solve a transport equation with a source (Is it still called transport equation?) using DSolve. The form of the source serves only as an example. It can ...
173 views

### Automatically tracing and keeping ViewPoints in a list while manually rotating 3D graphics

I will need to make a video from the manual rotation of a 3D graphics. In order to do this, I will need to record the set of all view points that I made during rotation. There is method that we can ...
1k views

### Left-aligned PlotLabel?

Is it possible to have the text generated by PlotLabel (or any other function) aligned to the left side of the plot instead of in the center?
I am now learning the Kalman filter and wants to implement it by hand to understand it better. To be specific I want to first simulate a sequence of data by  \dot x=Ax+Bw\\ y=Cx+Dv,\\ ...