Questions tagged [scoping]
Questions on Mathematica's scoping constructs (Block, Module, With, etc.)
1
vote
1answer
55 views
Using rules inside Module or Block
I have a rather long piece of code inside a Module, and I want to provide different parameters to the different pieces inside the ...
0
votes
1answer
48 views
0
votes
0answers
20 views
Gradient method in vectorfield on surface table does not work, module is slow
For teaching purposes I want to generate a vectorfield on a surface an visualize the path of the gradient method.
The surface and the gradient are generated by
...
10
votes
4answers
531 views
What is the accessibility of a package's `Private` context variables?
I've been reading up on how Mathematica handles contexts, $Context, $ContextPath, and a few of the tutorials they have on ...
6
votes
1answer
109 views
RegionPlot3D no longer localizes its arguments?
Bug introduced after 9, fixed in 12.0.
Just now, I was astonished to find the behavior of RegionPlot3D changes somewhere after v9 . Consider the following sample:
...
2
votes
1answer
65 views
How to trace value assigned to local variable(variables in Module)?
Bug introduced in v10.1 or earlier and persists through v11.3
CASE:4240757
Here is my code:
...
0
votes
0answers
48 views
Assigning values to variables inside Module using user defined function
Say I'm defining a function
with some local variables, for which I'm using Module. Now, I want to assign some value (or perhaps a list of values or a list of list, ...
1
vote
1answer
85 views
Why are there local variable conflicts in my recursive function definition?
Sorry to post a long piece of code. There are two places in here where I Print[] 'path2' when the count == 984, because for some reason, that list is getting ...
0
votes
1answer
73 views
Different result in ContourPlot function using different version of Mathematica (?)
I tested "Elasticity with Mathematica" notebook (Mathematica 6) in Mathematica 11.3 and tested C05_stress_kirsch.nb, I added some trigger code to protected function in the tensor2analysis.m file, and ...
2
votes
0answers
24 views
1
vote
0answers
45 views
Why doesn't `ReplaceAll` work in this situation? [closed]
I can work around this by using With, but it seems really odd to get the following:
...
0
votes
1answer
57 views
Multiple functions within a Module
I have a function that extracts a numerical value from two vectors, written as Spa[i_,j_]:=Flatten[LaU[i].LaD[j]][[1]]. (Note, I'm sure that this isn't the most ...
1
vote
0answers
51 views
Function returned from module doesn't work [closed]
I have a sequence of steps that work in the main notebook:
...
0
votes
1answer
58 views
Finding the inverse of a function
I am to solve for $r(\rho)$ given the function,
\[Rho]Asymp[r_,b_,q_] := 1/(1 - q) Gamma[1/(1 - q)]/Gamma[(q - 2)/(q - 1)] r Sqrt[1 - (b/r)^(1 - q)]
This can be ...
1
vote
1answer
30 views
Evaluation of Extract and use the result in a Sum
I am experiencing a problem in the evaluation of a sum. I hope that someone can help me, I am not an expert Mathematica programmer. I'm posting just the portion of code that gives problems, I know ...
4
votes
2answers
114 views
Scoping of pattern variables [duplicate]
I have run into a problematic behavior, and then came to find that it is a "possible issue" called out in the documentation, but I guess I am just baffled that this IS an issue, and am wondering why. ...
0
votes
1answer
128 views
Can I bake my own PI using your Wolfram language oven and prebuilt utensils? [closed]
How might I override the value of the Greek letter PI within various builtin language functions in the Wolfram language? Specifically and without having to reinvent the wheel or code equivalent ...
2
votes
1answer
51 views
How to define a function inside a module through Evaluate [duplicate]
I am trying to define a function inside a module as following
...
0
votes
0answers
46 views
Symbol created in Module not seen outside of Module scope [duplicate]
I am using a function defined with a Module[]. In the Module I am creating a new variable name using a ...
1
vote
0answers
52 views
ConditionalExpression still resulting from Assuming a Module's local variables
I have a memoizing, recursive function whose MWE looks like this (the two fake inputs/ICs are from 'K' and 'Bfun2', the latter just a quick way to check the results coming out of the Residue.:
...
1
vote
2answers
81 views
How do I localize changes to a variable inside a Do-loop?
I want to change the increment value inside the do loop . But i dont know why it remains for the first declared value?
...
3
votes
3answers
98 views
MostOccuringWeekdays Wolfram Challenge [closed]
I am working this challenge from Wolfram Challenge. I believe that I have solved the problem with the following code (note it is not very efficient - I am new to Mathematica!)
...
3
votes
1answer
52 views
Module - Symbols out of scope of lexical scoping
The Problem
Consider the following code (1):
In[1]:= x = 2;
Module[{x, y},
y[x_] = x;
y[1]
]
Out[2]= 2
I expected the answer ...
3
votes
3answers
220 views
What is wrong with Module? or me? [closed]
The following code does not give me an answer. It looks all is working when each command inside Module is individually run. But ...
2
votes
1answer
42 views
Why does Mathematica stay on an endless evaluating loop with Manipulate?
I have built Manipulate to see the impact of a change in time and volatility to the profit of an option strategy, bull spread.
To calculate the price of the option, I built the good old Black-Scholes:
...
5
votes
1answer
129 views
With vs. Block scoping of parameters for Plot
A very basic question..
Why does Block work, but not With, to specify value of a parameter for a function to be plotted?
...
5
votes
2answers
73 views
HoldAll Attributes and Delayed Evaluation: ContourPlot with solutions to NDSolve
This is a general question on evaluating functions that are defined to be evaluated with delay.
In particular, I am having difficulties working with the ...
1
vote
3answers
69 views
Prime number counting function
As part of an assignment for a calculus class, I have to write code for the prime number counting function $p(n)$, I have no problem creating the function itself, but for I want it as a function, ...
6
votes
0answers
62 views
Nested rules and automatic renaming of variables [duplicate]
I understand why $ happens here:
ClearAll[foo]
foo[a_] := (x_ :> a x)
foo[1]
...
0
votes
0answers
38 views
K vs k in a module
Module[{K = 1, fn}, fn[p_] := Print[K];
ParallelTable[fn[p0], {p0, 2}]];
Prints K$316 (or whatever the module counter is on)...
1
vote
0answers
48 views
What use is empty binding list in `Block[{},…]`? [duplicate]
Spelunking the Export function, I stumbled upon the following definition:
...
1
vote
1answer
65 views
1
vote
1answer
58 views
Problem passing argument in hash table from global context to a module
I was experimenting with passing arguments via a hash table to a module. Found a very strange result. When I pass a function to be plotted inside the module, it comes out empty.
Yet all argument ...
2
votes
1answer
72 views
Module and With do not work in some cases
I apologize if the title is too vague/general but I couldn't find a better one. I am trying to use either Module or With but it does not work if the object containing the local variables is defined ...
7
votes
0answers
124 views
A bug in Derivative?
Update
This is a bug in v11.3 or earlier and is fixed in v12.
Original Post
Check this out:
...
0
votes
1answer
71 views
Want help with debugging a For-loop
I'm trying to run a simulation, which at the end gives a value 'qber'. Now I want to run this simulation multiple times with different values of 'p' each time. And these value of 'p' are actually the ...
2
votes
2answers
124 views
Clear variables inside Module
I have a function that uses Module. The function takes as input a .csv that can have as many columns as it wishes to, and it ...
5
votes
4answers
208 views
Create rule whose LHS is already defined
My question will be clearest if defined using an example. Consider the following code:
Func[k_]:=Block[{a},
a[t_]:=t^k;
{a[t]->a[t]}
];
However, calling ...
1
vote
0answers
44 views
Dependent variables in With operator [duplicate]
I want write something like this
With[{x=1, y=x+1}, y]
and get 2 as an answer. What is the correct way to do this?
0
votes
0answers
36 views
How to speed up a module function with a large number of arguments?
I'm setting up a fairly hefty numerical code dealing with matrices
of variable dimension, but on the order of hundreds of rows and columns.
I'm using a Module format:
...
1
vote
2answers
123 views
function fails to use local variable when it is called inside a Module
I have these two functions fun and microstep.Fun makes use of a Module construct within which I define the ...
0
votes
0answers
34 views
0
votes
0answers
59 views
Iterating a Module
I have a Module that can act on other Modules, which is given as
Kk[EE,p,z1,z2,z3,K_func]
and I am trying to iterate it, such that
...
0
votes
0answers
23 views
How to define a global function dependent on a local pattern? [duplicate]
When g is in the local scope defined by Block, the following fails:
...
2
votes
2answers
45 views
Table and evaluation order
I thought Table should not evaluate the inner code until it inserts the value. I'm confused by
test1[3]="a";
test2[4]="b";
Table[DownValues[i],{i,{test1,test2}}]
...
1
vote
1answer
49 views
Manipulating definitions while reading them with Get
In order to read in a definition with certain parameters replaced by appropriate values I can use for example
Block[{a=1.1,b=2.2}, Get["file"]]
where ...
2
votes
3answers
251 views
Use of Module With Functions
Really confused by how one should use the Module[] command in two variables. For example my function here should return the ...
0
votes
0answers
30 views
Tracking System function (Get) calls, and Stack[_]
Consider the following attempt and variations thereof to track (nested) calls to Get (reasoning of this approach below):
...
3
votes
1answer
83 views
ThrowAway Environment and Scoping
I want to be able to Get a .wl file. Run some functions (who will do their job working on some separate files that are being written away). And then return to some clean slate so that I can repeat ...
0
votes
1answer
28 views
Issues with Manipulate and dynamic variables in plotting [duplicate]
I'm trying to make a manipulate that shows a parametric plot of a cycloid with manipulators that affect the shape of the curve. My problem seems to be my scoping of the variable ...
