Questions on Mathematica's scoping constructs (Block, Module, With, etc.)

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0
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3answers
146 views

Clean-up Code / Reduce variables

I'm writing a playing card simulator of sorts, and everything works fine, but some Modules use a disgusting amount of variables. For Example: ...
4
votes
1answer
94 views

Dial control for Manipulate?

I'm trying to make a control item in a Manipulate that is a simple dial. I'm trying to mimic Manipulate[theta, {theta, 0, 360}], ...
7
votes
1answer
208 views

Returning a value from a Module

In the following simple example MyMod := Module[{i}, Do[ Return[1], {i, 3} ]; Print["test"] ] I expected the module to exit on ...
4
votes
2answers
164 views

TrackedSymbols affected by CurrentValue. Another problem with SetDelayed(:=)+OwnVales in Initialization

It is MWE, only a Disk[] that should print "Click" when clicked. Also "date... updating" ...
5
votes
1answer
136 views

How to inherit options by scoping?

Consider the following example: you have a function framed producing a cell with a button that, when pushed, calls framed again. ...
0
votes
1answer
110 views

Why do InputFields not respond in Manipulate utilizing FindGeometricTransform?

In the following code changing the InputField does not result in observing changes in a result from FindGeometricTransform, but ...
0
votes
2answers
165 views

Defining Piecewise Functions in Modules

In short, my question is the same as my previous one except that everything is now wrapped up in a module. The relevant code I'm working with is: ...
2
votes
0answers
37 views

Differences in SetDelayed (:=) in Module and DynamicModule [duplicate]

I have a question about the differences in SetDelayed assignment functions in a Module and in a ...
2
votes
2answers
102 views

DynamicModule with intermediate expressions

I am trying to generalize a Manipulate construct into a DynamicModule one to try and include smoother controls, but I seem to be ...
7
votes
1answer
229 views

Variable scoping in Module

I don't understand why $a$ and $b$ are not local in the following code: ...
0
votes
0answers
91 views

Local variable names - Is there an easy way?

I apologize first, because this has been asked, like in Treat all variables as local in a module [duplicate] Variable scope similar to other languages But I don't get how to use them. Some codes ...
0
votes
0answers
25 views

How to pass rules to packages [duplicate]

EDIT: After helpful comment from @Mr.Wizard I added the working implementation below for future reference. I wrote a module that does something with variables provided in form of a rule. It works ...
6
votes
1answer
64 views

How to reset the $ModuleNumber?

According to the documentation, we can reset $ModuleNumber to a positive machine integer. There is even an example in the doc: ...
0
votes
2answers
109 views
0
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1answer
79 views

Circumventing the default scoping: Assign a variable inside a function [duplicate]

I'm currently trying very hard to assign a variable inside a function. Therefore I'm using a function like this, which should reassign a predefined variable. ...
3
votes
1answer
62 views

Pathological behaviour when evaluating a sum

When I declare the function $f$ as follows: f[n_] := Sum[x/Sum[Sqrt[y], {y, 1, x}], {x, 1, n}]/n the input ...
5
votes
1answer
167 views

Treat all variables as local in a module [duplicate]

In most languages, any variable defined inside a function is considered local. ...
2
votes
2answers
124 views

Getting variables out of Dynamic Modules after restoring the program

The scrap of code below [from Mathematica's Help on DynamicModules] generates a Pane of ...
0
votes
1answer
200 views

Passing lists to functions in a manner that works like pass-by-reference in other languages?

Is it possible to use a list as a variable, i.e., to pass it by reference to a function? In particular, I have a two-dimensional array and a function to get one element specified by its position: ...
16
votes
2answers
262 views

Module trash collection behaviour

I have asked this question before on the Wolfram community forum (http://community.wolfram.com/groups/-/m/t/83845?p_p_auth=Gxoxe65B) but not with great success. Module creates temporary variables of ...
1
vote
1answer
141 views

Passing a joined list of symbols for Module or Block to treat as its own local symbols

The Question I'd like to write a function which itself takes a list of symbols, e.g. Foo[{x, y, z}] to pass to Module ...
7
votes
1answer
116 views

Strange behaviour of Internal`InheritedBlock

I was going to post an answer for fast way to replace all zeros in the matrix. I was even quite happy because timings were the same order of magnitude as others. The idea was to overwrite ...
11
votes
4answers
312 views

Using With to scope over pure functions

Consider this example: given an option for a function func as "x" :> (a&), how can one assign different values to ...
0
votes
0answers
95 views

Programming a Meijer G related result

I am not that new in Mathematica, but I do not remember I have ever used it for programming (like we may do in Java). I have an important result given here by this integral: $$ \int_0^{+\infty} ...
3
votes
1answer
168 views

Namespaces in Mathematica

In many programming languages one can define a namespace with namespace abc How can the similar be done in Mathematica? The ...
3
votes
2answers
203 views

How to declare a function that uses local variables of a module outside this module?

I have the following code Module[{f,x=0}, f[t_] := x + t; ..........; ...f[1]...; ..........; ] My aim is to put the declaration of the function ...
4
votes
3answers
94 views

Creating a function after working out an example calculation

I have created this setup, it is giving me the correct answer, however I am interested in a function that does all this calculations and creates a output of mean and standard deviation. The function ...
2
votes
1answer
120 views

Module Inside ToBoxes or MakeBoxes

Does someone mind explaining why Module doesn't seem to work while inside ToBoxes or MakeBoxes. ...
1
vote
2answers
158 views

Confused about scoping, not sure what to ask

I'm grading for a class using Mathematica right now, and one of the students ran into a weird issue. When he ran code like this: ...
6
votes
1answer
135 views

Creating a Block from a list of rules

How can I create a function which works like Block but takes a list of rules as its first argument, rather than a list of assignments? The function needs to be ...
13
votes
3answers
349 views

Variable scope similar to other languages

Mathematica, unlike many other languages, defines the variables in the global scope unless it is explicitly asked to define a variable in a local scope, e.g., using ...
7
votes
0answers
262 views

Compile recursive function modifying global variables

How to compile recursive formula when it relies on more than a few global variables (global to the topmost compiled function)? It is unreasonable to pass on all such variables to each recursive ...
0
votes
1answer
100 views

Arbitrary number of variables in Module, Block, etc

How do I specify an arbitrary number of variable names and initialize them inside of a Module or Block? For example, I want to do something like: ...
0
votes
1answer
80 views

Scope of expression in a user-defined function

I have the following code: fbasic = A + R + Z*Z *Z*Z; f[A_, Z_, R_] := fbasic + R; f[0, 2, 3] The answer I am getting is ...
7
votes
3answers
534 views

What is the right way to construct DynamicModule

When I'm creating DynamicModules for CDF purposes I'm usualy basing on my experience with that, particular goal and content rather than on deep insight. I want to ...
2
votes
1answer
261 views

Call Functions From File Without Modifying Context (Sandbox)

Let's say I have file named test.m containing test[arg1_] := ( Print[arg1];) What is the best technique for calling test like ...
1
vote
0answers
129 views

Variable scope in nested NMaximize, NMaxValue

I'm trying to use NMaxValue inside other statements (FindRoot and NMinimize). Those statements should bind variable names, but I'm getting weird warnings which seem to indicate that the variables ...
9
votes
1answer
128 views

What are the scoping rules for function parameters shadowing System` symbols?

Here are some very contrived code snippets, highly unlikely to appear in real code, but still I am curious why they behave like this: ...
5
votes
0answers
112 views

Are there any videos that show how different Mathematica expressions are evaluated?

Are there any videos that show how different Mathematica expressions are represented internally as object graphs and demonstrate how they are transformed during an evaluation? I am asking because I ...
8
votes
1answer
141 views

Is it possible to write a function immune to symbol redefinitions in any Block surrounding its invocation?

Normally, semantics of symbols used in a function definition can be changed by their redefinitions in Blocks surrounding the function invocation: ...
3
votes
1answer
147 views

Issue with scope of variables

For the definitions, t = 1; f[x_, y_] := t (x + y); v[3] := {1, 1}; g[u_] := f[v[u][[1]], v[u][[2]]]; the following two expressions yield different results, ...
8
votes
1answer
122 views

Is it possible to use the global definition of a symbol as part of its new local definition set in a Block?

Consider the following expression: Block[{Print = CopyToClipboard}, doSomething[]] Now all calls to Print from ...
2
votes
1answer
152 views

Effect of Block[] on iterators in Manipulate[]

The following is a toy example that hopefully shows the problem clearly enough. Why does the following code create a nice, manipulable output: ...
7
votes
1answer
182 views

FullDefinition and Module local variable

I have a question about FullDefinition and how it interacts with the local variables of Module. I've created a few functions ...
2
votes
1answer
125 views

Odd edge-case behavior of Block

In this example, Block is used to localize the variable cache as used in the function g when called from the function ...
3
votes
1answer
163 views

How can I set multiple values to local variables in a Module?

Multiple assignment is supported by Set. How can do something similar in Module expressions? If I could do it, whould there be ...
24
votes
1answer
228 views

What does Internal`InheritedBlock do?

What does the function Internal`InheritedBlock do? How is it different from the regular Block?
4
votes
3answers
185 views

Modify this code using Module and While

I have written a recursive function and would like to re-write the code using Module AND While to compare the timings. Here is my recursive function for f[n], where 6 n f[n] = f[n-1] + n! for n>0 and ...
6
votes
2answers
210 views

Variable scoping problem when mapping over delayed replacement

This is something that got me curious while I was playing around with Mathematica. Consider the following (contrived) example: ...
9
votes
0answers
152 views

Compile not correctly initializing a variable defined inside Module

In the following example, inside the minimumX's Module, x is initialized to 1, but the ...