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

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2
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3answers
50 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... ...
0
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0answers
13 views

Trouble picking up package definitions [duplicate]

I open a new notebook and type ClearAll[test]; test[x_] := x + 42; I save it as Temp.nb and also as ...
1
vote
2answers
43 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 ...
1
vote
2answers
212 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. ...
1
vote
2answers
55 views

why the variable scope is not local when using evaluate to plot multicurve?

I noticed a surprising problem when using evaluate to plot multicurve, "evaluate" function actually consider global variable first, not the local! I can illustrate the problem using the following ...
10
votes
2answers
357 views

Syntax highlighter shows error for Manipulate when it's inside a Block or a Module

I'm putting my new copy of Mathematica 10 through its paces and I noticed a weird change in the colouring scheme that I find very annoying, and I'd like to get some insight into why it's happening. ...
-1
votes
2answers
71 views

How to fix the “Module” function, for implicit funcitons? [closed]

I wanted to make a function which gives the frequencies of a number in a specific list, when I came accros this problem. This is what I tried: ...
2
votes
1answer
41 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 ...
1
vote
1answer
45 views

How can I change the scoping of a pure function returned by a function in a package?

I have written a small Mathematica package that contains a module that solves some differential equation with initial conditions. Suppose that the solution to this differential equation defines some ...
1
vote
0answers
41 views

Settings to disable global scope

I am building a fairly large application in Mathematica, and globally scoped variables are causing issues. I would like globally scoped variables to be out-of-scope for my expressions, except by ...
1
vote
0answers
69 views

How to implement nested With as a single construct using functional programming (Fold)?

It is possible to define my own With construct where each local constant can depend on the previous defined local constants? I wish to replace something like this ...
5
votes
2answers
122 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: ...
0
votes
0answers
38 views

Scoping problem with Manipulate [duplicate]

Consider the following simple code: f = Sin[a x]; Manipulate[ Plot[f, {x, 0, 10}], {a, 0, 10}] Manipulate takes f to be ...
3
votes
1answer
82 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 ...
4
votes
0answers
96 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. ...
8
votes
1answer
105 views

Does the syntax coloring I see indicate a real problem?

I need a behaviour provided by: x = 2; Block[{x = HoldForm[x]}, x] x FrontEnd marks ...
1
vote
1answer
45 views

Replicability of RandomVariate within a function?

I have a rather basic question but can't figure out a foolproof answer. In the following code, I build a function which returns the mean difference between successive elements of a vector created from ...
5
votes
2answers
115 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: ...
3
votes
0answers
118 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 ...
0
votes
1answer
55 views

Change input variable in a function [duplicate]

I'd like to write a function, that would take a matrix as an input parameter and would change it by multiplying one of its rows by a factor. I try to do it in the following way: ...
0
votes
0answers
51 views

Fold Dynamic Function [duplicate]

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. ...
3
votes
3answers
98 views

Name scope confusion

Sorry for the too ambiguous title. First consider a following code snippet. ...
1
vote
2answers
89 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 ...
0
votes
1answer
80 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. ...
1
vote
2answers
110 views

`Slot` (#) interfering with evaluation

In the following I am using one function makeFunc to assemble two functions a[t] and b[t] to ...
0
votes
3answers
132 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
92 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
181 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 ...
0
votes
0answers
65 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 ...
4
votes
2answers
163 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" ...
0
votes
0answers
48 views

Dynamically Update Inset within Graphics with RunScheduledTask

I followed the instructions given below to play with RunScheduledTask within DynamicModule. ScheduledTask with scoped ...
5
votes
1answer
132 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
97 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
78 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
34 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
95 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
211 views

Variable scoping in Module

I don't understand why $a$ and $b$ are not local in the following code: ...
0
votes
0answers
87 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
59 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
90 views
0
votes
1answer
75 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
61 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
148 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
110 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
195 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: ...
14
votes
2answers
228 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
134 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 ...
6
votes
1answer
113 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
299 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 ...