Questions on the basic structure of the Mathematica language (Wolfram language) including atomic data types, syntax etc

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6
votes
1answer
298 views

What is the relationship between Thread and MapThread

I hope this is not a silly question, since there are plenty of questions on Thread and MapThread. However, I still cannot quite ...
12
votes
1answer
176 views

Is there a way to control which special forms Normal converts?

Normal documentation reads: Normal[expr] converts expr to a normal expression, from a variety of special forms. But is there a way to control which special ...
3
votes
3answers
206 views

How to assign symbols to functions

Several functions work with symbols in MMA: Take for example Part: l1=l2=Range[4]; l1[[3]] (*3*) l2[[4]] (*4*) I want to make ...
0
votes
0answers
46 views

Treating expressions as symbols [duplicate]

I'm trying to do something like this: test = {x, y}; With[{test[[1]] = 3}, x/y] However, the following error is printed: With::lvset: "Local variable ...
0
votes
2answers
46 views

Using Nest on a function that takes a function as one of its arguments [closed]

I have a function, nS[f_, xk_], which takes as arguments a function f and a vector xk. It ...
6
votes
0answers
174 views

Built-in symbols which are more close to the root/core of Wolfram Language

Seeing the vast scope of science covered by the Wolfram Language (WL) and the large amount of built-in symbols (functions), I am curious to know which built-in symbols are more close to the root of WL,...
0
votes
1answer
191 views

Solving a vector equation [duplicate]

I want a simple and intuitive way of solving for $t$ given that $\mathbf{i},\, \mathbf{j},\, \mathbf{k}$ are the unit vectors in $\mathbf{R}^3$. $$ 5 = (2 \mathbf{i} - 3 \mathbf{k} + (\mathbf{i} - \...
3
votes
1answer
95 views

How to deal with Part in a function?

I need to iterate several functions such as {3 x[[1]]^2 + x[[2]], x[[2]], x[[3]]}, {Exp[x[[4]]], x[[2]], x[[3]], x[[4]]},etc. ...
2
votes
1answer
95 views

Can I use Switch with an inequality? [closed]

I'd like to have something like: Switch[x, 10, a = 3; b = 7, >10, a = 5; c = 6, _, a = 7; d = 12, b = 1]; I can't seem to get this to work.
0
votes
1answer
97 views

solving quadratic and linear congruences with different modulus

We are able to solve the quadratic congruences $C^2 + Q^4 - 2\equiv mod 3072$ and $C - Q^2 - 2046\equiv mod 3072$ by entering ...
3
votes
2answers
101 views

How to use an expression for the argument to a function [duplicate]

I would like to define a function over a list of variables like f[a_,b_,c_]:=a+b+c However, when this list is big it makes uncomfortable to read. Can I somehow ...
2
votes
1answer
85 views

Expressing a definite integral as pure function with the upper-bound as it argument

Suppose i have an integral which has a closed form, $\quad \quad \int_{a}^{b} f(x) dx=F(a,b)$ I want to use output function $F$ as a pure function, like ...
1
vote
2answers
74 views

Perform operation on part of a table / create a reference

There is a function f that I would like to operate on a rectangular part of a table t. The part is specified by function ...
0
votes
1answer
135 views

Suppressing tiny imaginary parts in complex numbers [closed]

How do I extract the real part of a substitution expression from FindRoot or Solve? Or alternately, how do I insist that they ...
0
votes
1answer
93 views

Create an array with certain conditions and use it to fill a matrix [closed]

I am translating my code from Python to Mathematica. Here is a piece of my Python code: ...
1
vote
1answer
78 views

Defining a function of matrices [closed]

I am translating my code from Python to Mathematica. How can I define a function similar to the following: ...
3
votes
0answers
306 views

Minimalistic code challenge on Apollonian gaskets

I've been recently fascinated by the beauty, symmetry and mathematical richness of the Apollonian gaskets. So I felt myself challenged to see if it was possible to generate one in Mathematica with ...
0
votes
1answer
63 views

Generating comma separated input for LCM [duplicate]

I would like to calculate the Least Common Multiple of the 100 first numbers. I've tried with LCM[Table[i, {i, 10}]] But it produces a list instead of the right ...
3
votes
0answers
221 views

Mixing Wolfram Language & WolframAlpha Queries - How robust is it?

The advent of Mathematica in the cloud and linguistic input potentially transforms expectations of the Wolfram Language's programming model and its inherent robustness. An example of this comes form ...
7
votes
1answer
109 views

Context-dependent functions

TL;DR warning! My question is not about getting the length of the ticks correct (although if someone has good suggestions, that would be welcomed). My question is about constructing functions that ...
3
votes
4answers
227 views

How can I make a summary of all the commands of Mathematica?

I would like to have a simple way to get summary information about all the many commands built into Mathematica. How could I do this? Is there a site I may refer to?
0
votes
0answers
35 views

How can I change this function for the better? [duplicate]

I have a function for an lfsr (linear feedback shift register): ...
2
votes
2answers
163 views

Can a pattern examine all partitions of a sequence?

Say I have a list: {a, b, c, d}. I'd like to check that the list has some partition, say {{a, b, c}, {d}} such that all the elements of the partition satisfy a ...
11
votes
3answers
386 views

How do I make a string literal without having to escape backslashes?

I'd like to say something like: foo = @"\abc\def\ghi" instead of foo = "\\abc\\def\\ghi" How do I do this? This would ...
0
votes
1answer
71 views

Getting error Import::chtype when mporting 2D array of images [closed]

Suppose I have images = {{1.jpg, 2.jpg}, {3.jpg, 4.jpg}} Now I try to import all of them at level 2, ...
0
votes
1answer
57 views

How to destructure local variables?

Why can't I use this Where[{iw, ih} = ImageDimensions[i], ...] instead of this ...
0
votes
1answer
75 views

Permanently fixing a variable in the function

I need to define a function let's say f[x_, y_] := x^2 + y^2 such that I need to fix one variable (let's take y = a) and to ...
0
votes
2answers
103 views

Function that creates a table from two lists

I have two lists shown below: list1 = {(0,0,0,0),(0,0,0,1),(0,0,1,0),...,(1,1,1,1)} list2 = {1,5,5,5,...,5} How can I construct a function that outputs a table similar to this: $$\begin{array}{c|c} ...
0
votes
2answers
252 views

How to construct a linear feedback shift register

Are there any posts regarding the construction of a LFSR (Linear Feedback Shift Register) in Mathematica? I can't seem to find any and I am not sure how I would construct one.
0
votes
1answer
95 views

Built in function to convert list of numbers into list of binary numbers [closed]

Does Mathematica have a build in way to convert a list of numbers into a list of binary numbers? If not how can this be accomplished?
0
votes
1answer
133 views

Help with functions in Mathematica

I'd like to make a function that has many parts. Doing this in something such as Java, which I am familiar with, would be simple. In Mathematica I have these "pieces", which I want to put into a ...
2
votes
5answers
232 views

Making loop based off what I can say in words

I have a list of values a: {1,4,11,14} I want to print out values that satisfy b(1+a) = 0 mod 15 where b are the values from 0 to 14. The output I am wanting is ...
2
votes
3answers
99 views

Perform For-loop and show output which meets a certain criterion

I am new to Mathematica and I have a For loop like so: For[i = 0, i < 15, i++, PowerMod[i, -1, 15]] Currently it doesn't output anything. The calculation I am ...
11
votes
1answer
408 views

How to visualize pattern matching process?

I want a function that does the same job like ReplaceRepeated, and can make the matching process visible. I searched the Internet but didn't find any existing code ...
1
vote
1answer
144 views

Using FindMinimum with matrix input

I define the following function which spits out a number S when I feed it a dxd square matrix: ...
0
votes
0answers
57 views

Using NestList instead of Do [duplicate]

How can I express the following code using NestList: ...
11
votes
1answer
193 views

Copy Built-in function to new name

It is know that some built-in functions are system function and changing their properties may cause trouble. Suppose for example I want to change features of Cases: ...
4
votes
3answers
311 views

Manipulate: How to create custom reset Button automatically?

I have a complex Manipulate with more than 10 controls. Each one has its own default value. I'd like to add a custom button in the control area to reset all ...
18
votes
2answers
537 views

I define a variable as local to a module BUT then the module uses its global value! Why?

I have a question about modules and local variables. Here's my example: h = 5; Module[{a, h}, a[h_]= h^2; a[4]] (*Out[2] = 25*) I expected the module to ...
18
votes
1answer
402 views

Confused about how Partition works

I have a problem about the padding list about Partition command. For instance, ...
4
votes
1answer
182 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 ...
0
votes
1answer
1k views

How do I write nested for-loops?

Looking through the reference.wolfram, I couldn't see an example of how to write a multiple line "for" loop in Mathematica. I need to nest many for-loops in such a way I can do many things in the ...
5
votes
2answers
423 views

Code elegance and compactness. Help needed with Map, Apply

I need some help with code optimization and compactness. I have a set of two-dimensional points and I can use the Mathematica function FindClusters to find 4 clusters. I'd like to plot the points ...
2
votes
0answers
76 views

What was the thought behind the parallel versions of Table, Map, etc..?

There separately named versions of the parallel analogues of Map[] and friends: ...
1
vote
1answer
100 views

Computing a Sequence using Recurrence

I posted a similar question earlier today, but unfortunately I realized after several hours that I over-simplified the problem for this forum. There is a very good answer to the Computing a sequence ...
2
votes
3answers
134 views

Computing a sequence by recurrence

I am trying to create a list where each element of the list is calculated using the sum of all previous elements of the list and also uses the $N$th element of another list. The initial value of the ...
22
votes
3answers
754 views

Real Numbers in the Wolfram Language

Epilog: Much of the discussion in the answers below revolves around the distinction between Real as a data type and real numbers as a domain or class of numbers (irrespective of the form in which ...
19
votes
2answers
361 views

What does f_[whoCalled]^:=f really mean?

I came across the following post by John Doty in this Google Groups discussion: On Friday, January 11, 2013 8:23:16 PM UTC-7, amzoti wrote: It is clear the Mathematica uses Lisp as one ...
2
votes
2answers
109 views

DictionaryLoopkup - pattern specification

I would like to find all Italian words that have a specific pattern of letter repetitions. Actually I'm looking for 6-letters words that have 1 letter repeated 3 times, a second letter repeated two ...
3
votes
1answer
391 views

How can I trans-compile Mathematica into another language?

I'm looking for an exhaustive list of source-to-source compilers to all other languages, if any exist that is.