Linked Questions

534
votes
19answers
134k views

Where can I find examples of good Mathematica programming practice?

I consider myself a pretty good Mathematica programmer, but I'm always looking out for ways to either improve my way of doing things in Mathematica, or to see if there's something nifty that I haven't ...
46
votes
4answers
26k views

How to remove redundant {} from a nested list of lists?

There are numerous examples here, whose end result is the removal of empty brackets {} and empty lists. I still can't find an example of simply removing redundant ...
27
votes
7answers
1k views

How to perform a breadth-first traversal of an expression?

Mathematica provides functions that perform a depth-first traversal, or which use such a traversal, including: Scan, Count, <...
21
votes
2answers
3k views

Determine whether some expression contains a given symbol

Given a symbol t and an expression expr, how can I determine whether or not the symbol t ...
15
votes
3answers
979 views

substitution rules excluding subscripted variables

Suppose I have an expression containing p,Subscript[p,1],Subscript[p,2],etc. I want to ...
10
votes
4answers
340 views

Searching linked lists that contain lists?

Following the advice I've read here and other sites, I've been trying to use the Mathematica equivalent of a linked lists... ...
14
votes
2answers
429 views

Pattern to match L, but not L[_]

I have an expression where I want to replace L but not L[_] For example, the following doesn't work and ...
16
votes
2answers
526 views

ReplaceRepeated seemingly omits some rules

Is there a simple way in Mathematica to prevent rule reordering? Let me give an example: ...
7
votes
5answers
1k views

How can I name patterns in a Switch expression?

Suppose I have an expression and want to match it against successive patterns and return an expression corresponding to the first pattern that matched. In that case, I can use ...
5
votes
2answers
2k views

Using ReplaceAll to replace a head

Why would this work to replace the head b with newHead: ...
8
votes
3answers
218 views

Prevent testing Head with ReplaceAll

I have a list of strings list. I am trying to get rid of some elements that match string pattern patt: ...
14
votes
2answers
699 views

Understanding Villegas-Gayley

Temporary message: I have written another question about the behaviour the code by Oleksandr R. . Sadly I clicked "discard" and that was lost. I am a bit demotivated now and in order to not let the ...
8
votes
3answers
237 views

Preserve information in flattening a nested list

I have a series of lists in the form below: list={ {1,1} , {2,2}, {3,{3,1},{3,2},{31,{31,1},{32,2}}} } Its a nested list which the dimension is changing case to ...
5
votes
3answers
423 views

Replace x, but not x[a] [duplicate]

I want to replace all occurences of the symbol x with x[a], as long as it is not in the form ...
6
votes
2answers
230 views

Why the pattern match don't work as expected

When I try to figure out this problem,I write such code: ...

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