27
votes
3answers
871 views

Prepend Information to Warning Messages

I have a function running within a Do loop that sometimes issues a warning. I'd like to prepend the warning with the loop ctr so that I can go back and debug that instance later. Basically, I would ...
31
votes
4answers
760 views

How to make MapAt work with Span?

Span (;;) is very useful, but doesn't work with a lot of functions. Given the following input ...
37
votes
3answers
3k views

Antialiasing in 3D

Is it possible? Is it platform specific? Does it rely on the graphics hardware? Why does the antialiasing slider under Preferences > Appearance > Graphics do nothing? I remember seeing some ...
33
votes
2answers
2k views

Aligning plot axes in a graphics object

I need to align the y-axes in the plots below. I think I'm going to have to do some rasterizing and searching for vertical lines, then vary x and ...
29
votes
1answer
1k views

Customizing syntax highlighting for private cell styles

Is there any way to set up a cell style with a particular syntax highlighting? For example, I'd like to have a CProgram cell to write in blue the C special words. I have done it by setting ...
35
votes
1answer
633 views

What can I use as the second argument to Return in my own functions?

Having found out about the second argument to Return I played a bit with it, and the following tests all resulted in ...
33
votes
1answer
4k views

Does Mathematica support variable frame rate for any video format, in analogue of GIF-style “DisplayDurations”?

The good old GIF animation format allows us to set the duration of each individual frame in the animation separately. This is especially useful if some frames in ...
11
votes
5answers
3k views

How to find rows that have maximum value?

Suppose if I have following list { {10,b,30}, {100,a,40}, {1000,b,10}, {1000,b,70}, {100,b,20}, {10,b,70} } How to find rows that have max value in ...
12
votes
2answers
10k views

How to specify assumptions before evaluation?

If I request mathematica evaluate an integral for me, I'll often get a more general ConditionalExpression than I want. Example : ...
8
votes
2answers
316 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 ...
10
votes
2answers
2k views

Error entering equation in DSolve

I entered a command incorrectly as follows: DSolve[{y'[x]=y[x]},y[x],x] I am now experiencing: ...
65
votes
4answers
2k views
48
votes
9answers
2k views

Levels: how do they work?

I cannot understand how Mathematica manages levels, and so it's always a painful try-and-fail to use Flatten. Can someone please give me a very clear definition? ...
39
votes
4answers
5k views

Saving data inside a notebook so that I don't have to run it again?

Piggybacking on this, I am somehow not fully convinced that I can't save data generated by a calculation in a mathematica file so that when I re-launch said file, I wouldn't have to run my ...
57
votes
6answers
2k views

V10's Operator Forms - what are they good for?

V10 introduces an operator form for several functions perhaps primarily due to their role in queries as part of introducing data science functionality. At first pass it seems a lot of effort to add ...
33
votes
5answers
8k views

How to perform a multi-peak fitting?

I am wondering how to implement the multi-peak detecting and fitting in Mathematica. Following is an example of fitting the data using three peaks (such that the data ~ peak1 + peak2 + peak3). The ...
43
votes
3answers
3k views

How to find out which method Mathematica selected?

There are commands like NonlinearModelFit[] or NDSolve[] that have the option Method it ...
31
votes
5answers
1k views

What is the complete list of valid Front End Tokens?

What is the complete list of valid Front End Tokens? Preferably, by version number. Keywords: FrontEndToken, ...
20
votes
2answers
9k views

How to calculate contour integrals with Mathematica?

How to calculate the integral of $\frac{1}{\sqrt{4 z^2 + 4 z + 3}}$ over the unit circle counterclockwise for each branch of the integrand?
40
votes
2answers
1k views

Why does Simplify ignore an assumption?

Here is the example: Simplify[x + y, x + y == a] Simplify[x + y, x + y == 5] Mathematica 9 output: x+y 5 I expect the ...
25
votes
5answers
2k views

Partition a set into subsets of size $k$

Given a set $\{a_1,a_2,\dots,a_{lk}\}$ and a positive integer $l$, how can I find all the partitions which includes subsets of size $l$ in Mathematica? For instance, given ...
20
votes
3answers
5k views

About the number format in ticks

I want to LogPlot a function, but I have the trouble in the number format in the ticks. For example, ...
30
votes
4answers
7k views

Density plot on the surface of sphere

I would like to make density plots of a list of (size 2 or 3) spherical harmonics on the surface of a sphere. I'd like to plot it so that each element of that list is using a different color (red ...
17
votes
2answers
2k views

Open Excel file with Mathematica

I would like to open an Excel file and manipulate it as a COM object. While I'm able to open an instance of excel with ...
21
votes
2answers
1k views

How can I conveniently call igraph from Mathematica?

Mathematica has lots of functions for working with graphs and networks, but there are still some functionality holes that are provided by other packages. Also, due to the nature of graph theory, ...
27
votes
4answers
3k views

Is it possible to prerender animation in Wolfram Mathematica?

I have a DensityPlot which is evaluated for a long time. I wish to use it with animation, but it is absolutely inapropriate. Is it possible to render animation ...
23
votes
4answers
3k views

Can 2D and 3D plots be combined so that the 2D plot is the bottom surface of the 3D plot boundary?

I have a ListlinePlot function, that I would like to combine with both a Graphics3D plot and a ...
20
votes
4answers
3k views

Plotting piecewise function with distinct colors in each section

I have a piecewise function that I would like to plot but I was wondering if it is possible that each part of the function that is plotted when its corresponding condition is true be plotted with a ...
11
votes
5answers
5k views
17
votes
6answers
6k views

Replacing composite variables by a single variable

To replace a single variable by another variable, one can simply use the the replace all (/.) operator (e.g., ...
11
votes
1answer
7k views

Plot, extract data to a file

I need to save data that Mathematica uses inside the Plot command. The format that I would like to have is: x1 y1 x2 y2 ..... ...
15
votes
1answer
635 views

How get eigenvectors without phase jump?

I'm using Eigenvectors to get the eigenvectors for some matrixes, but the eigenvectors seems to have some phase jump. Here is an example: Say we have a 2 by 2 ...
5
votes
4answers
18k views

Creating a table/Matrix during a For loop

I have a For loop (with i as a counter), which calculates different values (y1, ...
18
votes
2answers
1k views

Plot Option Precedence while combining Plots with `Show[]`

I like to build sophisticated plots by combining simpler ones with Show[]. Typically this involves setting non-default Plot-Options with the different ...
12
votes
9answers
2k views

Fibonacci Sequence Generator

I'm trying to write a function in Workbench which will generate a Fibonacci sequence starting with F0 = 0 and F1 = 1. So far I ...
12
votes
3answers
563 views

Why do buttons with ChoiceDialog freeze the front end?

Pressing the button below will freeze my front end. An unpainted white dialog box comes up, then it completely freezes, and I need to forcibly kill the front end. CPU usage stays at zero during ...
8
votes
3answers
2k views

Using D to find a symbolic derivative

I need to do the following: Define a function Take the derivative of this function and have a look at the symoblic representation Substitute in some values With the bonus that I want to use the ...
9
votes
1answer
370 views

Confused by (apparent) inconsistent precision

$$ e^{\pi \sqrt{163}} \approx 262537412640768743.99999999999925 $$ E^(Pi Sqrt[163.0]) N[E^(Pi Sqrt[163.0]), 35] NumberForm[E^(Pi Sqrt[163.]), 35] returns ...
59
votes
3answers
5k views

Metaprogramming in Mathematica

Being functional, and having no "quotation", i.e. essentially treating data and programs semantically same, Mathematica seems naturally capable of doing metaprogramming. But could anyone construct a ...
58
votes
6answers
10k views
42
votes
7answers
24k views

Labeling individual curves in Mathematica

I need to create a plot for export and inclusion in a report. Is there a better way to label curves than PlotLegends? From what I've read and my personal ...
69
votes
3answers
2k views

Automatically generating a dependency graph of an arbitrary Mathematica function?

Has anyone written a function to pull the function dependencies of a function? That is, it would be nice to have a function that returns a list of function dependencies as a set of rules, terminating ...
33
votes
4answers
4k views

How can I make an X-Y scatter plot with histograms next to the X-Y axes?

I just saw a nice plot there: How could I implement that in Mathematica — by which I mean the plot structure, not so much the styling.
42
votes
4answers
6k views

How to change the default ColorData used in Mathematica's Plot?

This question leads on from the recent question What are the standard colors for plots in Mathematica? There it was determined that the default color palette used by ...
46
votes
5answers
903 views

Placement of Condition /; expressions

It is my practice to place Condition expressions on the left side of := and :> in almost ...
30
votes
2answers
1k views

Can a Trie be implemented efficiently?

What is the most space and time efficient way to implement a Trie in Mathematica? Will it be practically faster than what is natively available in appropriate cases?
31
votes
7answers
2k views

How to select minimal subsets?

I am a newbie, so please point me in the right direction if you feel this question has been answered somewhere else before. Here goes: Suppose I have a list like this: ...
24
votes
1answer
15k views

Is it possible to export the equations from Mathematica to MATLAB?

Is it possible to export the output expressions from Mathematica computations (e.g., equations) in valid MATLAB syntax?
26
votes
6answers
622 views

Constructing symbol definitions for With

I would like to be able to define two arrays, one containing symbol names and one containing the values of those symbols, for use in constructs such as With. For ...
27
votes
3answers
827 views

How to flush machine underflows to zero and prevent conversion to arbitrary precision?

I'm working on some pretty intense computation in Mathematica; when my code started running slowly, I tracked the source of the problem to Exp[]. I need to ...

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