Linked Questions

2
votes
2answers
85 views

How to make a contextual variable?

I have a question that would be trivial in OOP, but I am a newbie to programming in Mathematica, so I'm wondering how to deal with it. Basically, I want to create a package which basically involves a ...
6
votes
2answers
178 views

How to prevent Mathematica from complete evaluation of special functions?

Recently I tried to check a result of integration which should be a linear combination of the Riemann $\zeta\;$-function at various arguments, the coefficients of the combination being of primary ...
10
votes
2answers
179 views

Unexpected behavior when directly assigning to DownValues

I'm encountering some unexpected behavior when assigning to DownValues. When I assign two definitions for test[1] as below, ...
10
votes
3answers
523 views

Mathematica unable to solve easy differential equation $y''+y\,y'=0$ with initial conditions $y(0)=1, y'(0)=-1$

Trying to solve the following: DSolve[{y''[x] + y[x] y'[x] == 0, y[0] == 1, y'[0] == -1}, y[x], x] leads Mathematica to declare that no analytic solution exists <...
15
votes
1answer
331 views

Why do subsequent evaluations seem to be stopped by a False Condition (/;)?

Exploring another problem and this example of @halirutan, I came across an evaluation behavior I don't understand. When g[] below is evaluated the first time, <...
5
votes
3answers
165 views

Why does `Block` reset `Attributes`?

Not even "formal symbols" such as \[FormalX] are guaranteed to always be symbolic. Their Protected argument is forgotten when ...
5
votes
1answer
208 views

ConversionRules and style inheritance

Take the LaTeX-Article stylesheet stylesheet = FileNameJoin[{"Article","LaTeX-Article.nb"}]; Compare these outputs ...
5
votes
1answer
208 views

Multiple down-values with exactly the same lefthand side

I was working on an answer to this question, when I was sidetracked by what I bring up here. I wanted a function, which when given a string representing a binary number, would convert the string to a ...
18
votes
2answers
276 views

How to find out what files are touched when Get is called?

Is there a way to capture all package files touched whenever a package is called via Get, Needs, ...
5
votes
2answers
212 views

Capturing an F1

I teach an Intro to Mathematica course, and one of the things I try to reinforce early on is just how helpful Mathematica's help is. In the very first lab for the course, I even give the students a ...
1
vote
1answer
108 views

How do I extend (prepend or append to) an existing TagSetDelayed rule? [duplicate]

I have a TagSetDelayed rule associated with, say, tag: ...
18
votes
5answers
631 views

Prevent graphics from rendering inside a held expression

Assuming each odd line is input I would like the even lines to be the output of the following lines. In the above the Graphics are inside ...
31
votes
5answers
2k views

How to perform a depth-first preorder traversal of an expression?

Mathematica provides functions that perform a depth-first postorder traversal, or which use such a traversal, including: Scan, ...
102
votes
7answers
6k views

What is the most convenient way to read definitions of in-memory symbols when we don't have the source files? (Spelunking tools)

Note: I put Simon's implementation on GitHub. Contributions welcome! When trying to read the definition of already defined (package or built-in) symbols using ...
53
votes
5answers
1k views

Placement of Condition /; expressions

It is my practice to place Condition expressions on the left side of := and :> in almost ...

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