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

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5
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3answers
275 views

Notation for specifying transformation rules

I would like to have a compact notation for specifying conditions and results in transformation rules. Consider ReplaceAll: ...
5
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3answers
145 views

Prevent iterator name from being confused with symbol passed into function body

I have a massive amount of code with lots of Table and Sum inside a Module. Each with their ...
5
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1answer
232 views

Parts of Module body evaluated in external scope?

I have an expression that suggests that some expressions in a module body are dragging in definitions from outside the scope in a surprising way. First, consider a symbolic constant, ...
5
votes
2answers
129 views

Generating EventHandler using Table

I would like to change the edge color of a graph when double clicking on it, the following code works: ...
5
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2answers
123 views

Checkbox behaving weird when variables are local

I have a DynamicModule in which I need a checkbox with a Max in the dynamic part: ...
5
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1answer
221 views

A smarter nested With?

I often find myself writing code that looks a bit like this: ...
5
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1answer
140 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. ...
5
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0answers
114 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 ...
4
votes
3answers
95 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 ...
4
votes
2answers
272 views

Comparing LetL and Module efficiency

I was recently introduced to the LetL macro thanks to Leonid's answer to one of my prior questions. I was, needless to say, impressed by the simplicity of its ...
4
votes
2answers
169 views

A better way of handling Module output?

I am sure this has been asked before in a way or another. I need to Save or DumpSave some symbols that contain the result of ...
4
votes
1answer
84 views

Module does not remove a function definition

The following is a minor variant of the function uniqueTuples as given by Simon Woods in this answer. ...
4
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3answers
189 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 ...
4
votes
1answer
196 views

How to avoid conflicts between local variable names and symbolic arguments in Block constructs?

I am using Block inside the definition of some recursive functions. If the Block definitions use short variable names, like ...
4
votes
3answers
139 views

Altering values in Manipulate with dynamically generated controls

I have a Manipulate whose controls are generated based on a parameter in a containing Manipulate: ...
4
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2answers
166 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" ...
4
votes
1answer
98 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}], ...
4
votes
0answers
146 views

Exhaustive examples of variable replacement due to nested scoping constructs

Consider the following examples, where I have replaced dollar signs in the output by a D. ...
3
votes
2answers
97 views

Is there a way to localize Off[some::message]?

Is there a way to temporarily suppress certain messages, so that I could write for example (with made-up syntax for that feature): ...
3
votes
1answer
150 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, ...
3
votes
3answers
102 views

Name scope confusion

Sorry for the too ambiguous title. First consider a following code snippet. ...
3
votes
3answers
430 views

Defining a new Function using RegionPlot

I'm trying to make images like this: to illustrate 2D integrals to a calculus class. I used the code ...
3
votes
2answers
214 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 ...
3
votes
2answers
425 views

Local variables

I'm trying to use Modules together with functions. tmp2 = x^2 + 1; f[y_] := Module[{x = 1}, Evaluate[y tmp2]] This works when ...
3
votes
2answers
267 views

Why does the syntax highlighter color a local symbol red inside DynamicModule?

I am adding a Module inside DynamicModule here is an example (thanks to @rm-rf for this simple example) ...
3
votes
1answer
56 views

Should “counters” used in Do, Table, … within Module be declared as local?

I have little to no understanding of how Mathematica handles scoping, so the question may seem a little bit funny. What is the preferred way: ...
3
votes
1answer
69 views

Hiding body of a module or function in mathematica

Is it possible to hide the body of a module or function in MMA? For example I would like to turn this: myModule[]:=[{}, Body of module ] to: ...
3
votes
1answer
72 views

Evaluating arguments of module (inside compile)

Note: this is a clarification of 2 earlier unanswered questions, Compile issues, scoping and order of evaluation and Optimising a simple computation with vectors . The problem I have a list of ...
3
votes
1answer
89 views

How to localize symbols on the right-hand side of Rule when using ReplaceAll?

I am frustrated by the following: {1, 2, 3.0} /. a_Integer -> a + 1 The a on the left side of the arrow is localized and ...
3
votes
1answer
169 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 ...
3
votes
1answer
61 views

Defining a function that prints both the name and value of a variable defined locally within the calling function

To save time when debugging with Print statements, I'd like to define a function -- call it PrintVal -- that prints both the name and value of a variable defined locally within the calling function. ...
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 ...
3
votes
1answer
147 views

Downvalues vs. Scoping for Functions

Regarding my recent question on using a default value for a function argument when a pattern was not met yielded some interesting answers, but the general consensus was "Yes this can be done, but ...
3
votes
1answer
178 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
0answers
159 views

Module in numerical model for NonlinearModelFit is slow and leaks memory

I am trying to make a NonlinearModelFit where the model is the result of a numerical calculation. My code works, but it is very slow and also seems to have a memory ...
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 ...
2
votes
2answers
551 views

Scoping inside of Module and Manipulate

This is driving me nuts: I'm trying to control the parameters for a relatively large system of ODEs using Manipulate. ...
2
votes
3answers
93 views

Dependency injection - use a specific implementation of one function within another

Consider... f[x_]:=Body containing h[some args]... g[x_]:=Body containing h[some args]... However I want to define something like... ...
2
votes
2answers
105 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 ...
2
votes
1answer
52 views

How to protect function variables [duplicate]

I am sure this has been asked before, but I can't seem to find the right solution. I want a function to be the solution to a differential equation ...
2
votes
1answer
264 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 ...
2
votes
1answer
158 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: ...
2
votes
1answer
120 views

Implementing local variables of a recursive function with either Module or Block

First, some quick background: I have been eagerly learning Wolfram and Mathematica for two months now, and along the way have written about 250 pages of teaching material that has ballooned into a ...
2
votes
2answers
71 views

How can my Manipulate be aware of a local variable inside a nested Module

I have 3 sets of 5 x-y points: RandomInteger[10, {3, 5, 2}] I want to display only one set of points at a time, and use a slider to move on to show the next ...
2
votes
2answers
128 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 ...
2
votes
1answer
39 views

Substitution breaking the scope

A novice's problem, perhaps: it seems that /. substitution does weird things to the scope. ...
2
votes
1answer
106 views

Odd problem with Module

I've been having a strange problem with Module. Oddly it seems to be linked to my use of Import and then applying a function such as Flatten to my Import. I pasted images of my code and output ...
2
votes
1answer
121 views

Module Inside ToBoxes or MakeBoxes

Does someone mind explaining why Module doesn't seem to work while inside ToBoxes or MakeBoxes. ...
2
votes
1answer
86 views

How to make a code line dynamic in a Module?

The code line If[StreamPosition>0,Read[str,Record]] should be executed in a Module at first. The Module consists of a Slider and a Pane. The Slider ...
2
votes
1answer
45 views

ControlType -> None Vs. Module inside Manipulate (i.e. making everything local)

I'm building a program on another one made available in the Wolfram Demonstration Project. I've noticed that in the original code (working flawlessly) many variables were made local inside the ...