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

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4
votes
1answer
78 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
1answer
102 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. ...
3
votes
2answers
90 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
134 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
91 views

Name scope confusion

Sorry for the too ambiguous title. First consider a following code snippet. ...
3
votes
3answers
257 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
161 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
224 views

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 ...
3
votes
2answers
195 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
2answers
315 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
1answer
130 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
57 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
127 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
147 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 ...
2
votes
1answer
122 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
405 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
2answers
82 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
220 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
118 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
2answers
95 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
106 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
78 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
0answers
32 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
vote
2answers
142 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: ...
1
vote
1answer
124 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 ...
1
vote
2answers
64 views

Is it possible restore initial values after modify a control in manipulate?

I used to program in Visual Basic, but in Mathematica I have not seen some kind of restore default values after any user modification command in the Manipulate ...
1
vote
2answers
86 views

`Slot` (#) interfering with evaluation

In the following I am using one function makeFunc to assemble two functions a[t] and b[t] to ...
1
vote
1answer
164 views

Using block or module to free cache

I'm writing some code at the moment that schematically looks like: (set initial conditions for some differential equation for given parameters (M,R,...)) ...
1
vote
0answers
100 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 ...
0
votes
3answers
314 views

Constructing a list with a Module [closed]

I have build this simple module trying to construct a matrix via Table ...
0
votes
2answers
181 views

Why does my code return {Null, Null, Null}? [closed]

I have a module created which makes what I want, but at the end there are {NULL, NULL, NULL}. Why that? How can I prevent this NULL list? ...
0
votes
3answers
117 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: ...
0
votes
1answer
58 views

Don't pollute outside context when solving equation from the outside

This code works fine only if a is not defined in the outside context: ...
0
votes
1answer
55 views

Multiple Simulations of a Markov Chain

I am trying to create a simple series of Bernoulli bits whose probabilities follow a two-state Markov chain. ...
0
votes
1answer
181 views

Why the dollar signs when I Solve inside a Module [closed]

I would like the solutions of my equations to be local only, so I did a Solve inside a Module: Module[{a, b, c}, Solve[{a == 3* c, b == 2 *a}, {a, b}]] and the ...
0
votes
1answer
124 views
0
votes
1answer
64 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. ...
0
votes
1answer
186 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: ...
0
votes
1answer
83 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
2answers
72 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 ...
0
votes
1answer
86 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
54 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: ...
0
votes
2answers
71 views
0
votes
0answers
42 views

Fold Dynamic Function

I'm making on a demo working with differential equations as functions of two variables (x and y). The demo will have to Fold the differential equation with an initial y-value and a series of x-values. ...
0
votes
0answers
46 views

Accessing variables outside DynamicModule

I have this DynamicModule which is basically a form of input fields that are parameters. My two final functions are H1 and ...
0
votes
0answers
42 views

Dynamically Update Inset within Graphics with RunScheduledTask

I followed the instructions given below to play with RunScheduledTask within DynamicModule. ScheduledTask with scoped ...
0
votes
0answers
82 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
23 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 ...
0
votes
0answers
71 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} ...
0
votes
0answers
64 views

What's the best practice for nested local constants? [duplicate]

Possible Duplicate: How to avoid nested With[]? I have many situations where I have a constant that is local to a function, with other constants that are computed from it. I see that I can ...