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

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5
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1answer
218 views

A smarter nested With?

I often find myself writing code that looks a bit like this: ...
5
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1answer
85 views

Temporary variable not removed in Mathematica 10

In Mathematica 10, the documentation still states that a symbol with attribute Temporary will automatically be removed when it is no longer needed. Now consider ...
5
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1answer
138 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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1answer
174 views

Treat all variables as local in a module [duplicate]

In most languages, any variable defined inside a function is considered local. ...
5
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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 ...
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 ...
4
votes
2answers
268 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
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2answers
156 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
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
192 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
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3answers
127 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
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" ...
4
votes
1answer
96 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
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0answers
135 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
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2answers
96 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
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1answer
149 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
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3answers
101 views

Name scope confusion

Sorry for the too ambiguous title. First consider a following code snippet. ...
3
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3answers
417 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
209 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
418 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
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2answers
259 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
54 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
63 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
66 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
88 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
166 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
55 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
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1answer
172 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
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0answers
62 views

How to assemble and disassemble a function into steps

I've watched many programmers (both novice and expert) write functions in Mathematica and have observed a common behavioral pattern. This pattern has many elements that would be automated and thus ...
3
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0answers
153 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
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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
540 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
91 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
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 ...
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
155 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
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1answer
90 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
126 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
104 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
120 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
92 views

Manipulating parameters in a complex algorithm

I have a complex algorithm that depends on: A wavelet basis A number of sampling points out of a distribution A thresholding value I want to be able to play with different scenarios using ...
2
votes
1answer
46 views

Is the use of Block to temporarily override definitions inherently unsafe? [duplicate]

This may have been discussed before, if so, please let me know. Consider the following example: x = 5 Dynamic[{Clock[], x}] This will always display the ...
2
votes
0answers
83 views

Compile issues, scoping and order of evaluation

I have a few questions about compiling functions, which I think are all related to scoping and order of evaluation. I will illustrate them by a minimal example of the problem I have. I'm sorry for ...
2
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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 ...
1
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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: ...
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2answers
247 views

Error with “Newton's method” in Wellin's Mathematica book

In Wellin's Programming with Mathematica book, here's one of his implementations of the Newton method, where the iteration runs until the error tolerance is reached. ...