Questions tagged [assignment]
For questions relating to assignments to symbols, patterns, or expressions.
268
questions
3
votes
1
answer
43
views
Choosing numbers whose divisors can be partitioned into subsets having the equal sum
How can we find the list of natural numbers between 100 to 10000, whose positive divisors can be partitioned into three subsets such that sum of all the elements in three subsets will be equal?
- 39
4
votes
1
answer
128
views
Choosing a subset of a set based on the sum of its elements
How can we choose a subset of a set based on the sum of the elements of the subset?
For instance,
n=6
dn=Divisors[n]
sn=DivisorSum[n,#&]
Is it possible to ...
- 41
0
votes
0
answers
52
views
Assign different type of balls into output containers with constraints
The problem is to asssign all differend kind inputs to outputs.
For example colored balls.
On the input we can receive max 5 different type of colored balls any with amount.
The amounts for the inputs ...
- 1
1
vote
0
answers
47
views
several actions inside If condition [closed]
Trying to write code with If, if it is correct to perform a number of actions.
I am a beginner user in mathematica and not sure the form of writing are correct.
What I'm asking in simple, this is the ...
- 215
1
vote
0
answers
45
views
How can I access to the needed part of this expression? [duplicate]
I have defined a list like this:
F[1][t] = ConstantArray[a1, 10]
Now I want to assign to some of the elements the value 1; I ...
- 6,104
0
votes
1
answer
45
views
Program works, but then fails when I write it inside Module [duplicate]
I'm new to Wolfram Language; I'm trying to get used to it by writing a bunch of code and programs, being one of them the algorithm for the bisection method.
When I write the algorithm outside of a ...
3
votes
2
answers
132
views
How to make c[n_, x_, y_] := ToExpression["p" <> ToString[n]] = {x, y} work?
I am trying to do the following:
c[n_, x_, y_] := ToExpression["p" <> ToString[n]] = {x, y}
That is: Evaluating ...
- 4,791
0
votes
1
answer
63
views
Forcing mathematica not to substitute some terms in an expression
I have an expression c which should be defined before the function and a function f defined as follows:
...
- 340
1
vote
0
answers
79
views
Extracting expressions from LHS of an assignment
I need to list all variables in a notebook containing several Set assignments, lhs=rhs, and equations, ...
- 433
0
votes
1
answer
67
views
NIntegrate seems to not recognize multiplication of Piecewise function and f[t_]:= function, Why?
Considering inputs:
vti={0, 1.5, 2.4, 5.0675, 7.735, 10};
Vscc=1.5; PSA=0.025; f=0.6; m=10;
I defined a function "pwtemp2", using "FC1" and &...
0
votes
0
answers
73
views
Can't create matrix function of symbolic functions and assign values to elements
So I have a problem regarding the symbolic matrix value assignment.
Say I create a matrix function as:
P[t_]:= {{P1[t]}, {P2[t]}, {P3[t]}};
Then I want to assign ...
0
votes
0
answers
53
views
How to use Mathematica to return value from for-loop [duplicate]
I tried to use Mathematica to implement random generator. The pseudo code I use is as following:
...
- 47
0
votes
1
answer
48
views
any way to store the values of the controls of a Manipulate so that one can reuse them in the future excutions
I’m using Manipulate[] to adjust several parameters, which will eventually generate some figures. After I get the desired view, I’d like to store the set of control parameters so that I can reuse them ...
- 675
0
votes
0
answers
53
views
Block Behavior, but for Function Assignment instead of Variable Assignment
We can define a function using a variable b that does not appear as an argument, and then using Block, change the output of the ...
- 1,547
2
votes
1
answer
164
views
Cannot assign variable value inside Do Loop
This is more of a conceptual problem.
Suppose I have three lists.
x1 = {1, 2, 9, 10};
x2 = {5, 6, 7};
x3 = {9, 10, 13};
Now, I wish to keep only the first two ...
- 1,018
0
votes
1
answer
62
views
Avoiding For loops to perform an assignment to a variable with indices of user-choice [duplicate]
I am looking for an efficient way to perform the following operation without For loops
...
0
votes
0
answers
37
views
Going between assignment rules and functions
I am trying to develop a model using Mathematica, and continuously run into difficulties going between the outputs of various functions (Solve, Differentiate, etc.) and back to functions (in the ...
- 3
4
votes
2
answers
90
views
Assignment with Span to Indexed Variable
If I use span to assign a value to every element in a "column", it miraculously works:
...
- 1,393
2
votes
1
answer
175
views
How can I list the common elements of two lists?
The elements of both lists are given as
A={9,5,9,3}, B={9,9,5,5}
In this case, how can I list the list {9,5,9} of the common elements of the two lists?
(The order does not matter.)
- 1,091
1
vote
1
answer
100
views
pure function assignment
I do not understand this statement from the Introduction to Dynamic tutorial:
...
- 11
2
votes
0
answers
58
views
Certain plotting functions are setting variables unwantedly
I came across the following problem. Certain plotting functions set variables to values, which I do not want. For example, if I run SliceVectorPlot3D with an ...
- 43
2
votes
1
answer
56
views
How can I transform equation results into an array of values? [closed]
I would like some help. I executed the following code:
Solve[Det[(s IdentityMatrix[2]) - A] == 0]
which yielded the following results at the output:
...
- 31
0
votes
0
answers
61
views
Proper way to construct a function that takes too long to plot and integrate
Consider the functions phi[t_] and psi[t_] defined in the code below. These are used as basis functions for interpolation ...
- 745
1
vote
0
answers
80
views
0
votes
0
answers
26
views
Extract actual result from equivalence [duplicate]
When I get a result like this {x -> -0.5 - 0.866025 I}, how do extract just the number: -0.5 - 0.866025 I. I can do this with the .rhs() method in Sagemath but I can't find the function in ...
1
vote
1
answer
50
views
Why does the delayed functional assignment evaluate to `5=6`? [closed]
Why is it that
x=5
x=x+1
nicely evaluates to 6, but the following
...
- 229
2
votes
0
answers
66
views
Referring to matrices with index [closed]
For exampe I have two matrices, with index 1 and 2
Mat[1] = ConstantArray[0, {2, 2}]
Mat[2] = ConstantArray[0, {2, 2}]
I wanna assign new value with
...
- 701
2
votes
2
answers
142
views
How can I get output from Reduce assigned to a variable? [closed]
I use Reduce to solve an 3rd order equation, and the output is given as the OR'd combination the solution variable. Normally, I can do a replacement to assign the value to a variable, but that doesn'...
- 187
1
vote
1
answer
49
views
How to list automorphisms on a finite set and analyze them
Let s be a finite set of integer lattice points, for example s = { {0,0} , {0,3} , {1,1} , {0,2} }.
I am trying to do two things:...
0
votes
4
answers
68
views
1
vote
0
answers
50
views
Errors with assigment and no errors with replacement rule, why? [closed]
So I have an expression, let's call it f11 which is a function of t of this form f11= a1*t^(-4)+ a3*t^(-3)+... and so on up until a finite positive power of t. In ...
- 165
0
votes
1
answer
44
views
0
votes
3
answers
82
views
Assign value to the symbol returned by function
Ok, so here is example code:
Clear[p, flag, k];
p = 2;
k = 1;
flag = True;
If[flag, p, k] = 0;
p
After that I get the message
...
3
votes
2
answers
145
views
Set value in a list at given position
Consider
r = Array[Total[{##}] &, {3, 3}]
(*{{2, 3, 4}, {3, 4, 5}, {4, 5, 6}}*)
pos = {{1, 1}, {2, 2}};
vals={100,200}
This
...
- 902
0
votes
2
answers
84
views
Using a list as arguments in a function
This might sound a little silly question but I cannot get my code work. Here is the problem:
I have quite a few lists of data which are basically beam profiles. I am using ...
- 37
2
votes
1
answer
57
views
Number of values stored in a function
Suppose I run this:
f[0] = 1;
f[n_] := f[n] = 2 f[n - 1];
f[1000]
Now there will be 1001 values stored in f, and ...
- 1,055
1
vote
2
answers
43
views
How can I use Part Assignment to change sublists into other sublists (without changing levels)?
Here's a 5x5 grid. Using predefined starting points, I'd like to change some sublists into something else (e.g., the values for a color, "drawing an opaque box").
...
- 73
3
votes
3
answers
516
views
Changing value of specific element in an array. (Converting code from MATLAB to Mathematica)
Can we change the value of a specific element of an array in Mathematica?
Basically, I have the following given MATLAB script which writes a big 3N-by-3N matrix $h$ by combining two 3-by-3 matrices $...
- 153
1
vote
1
answer
64
views
Scan and Set over multi-dimensional data
Suppose I have the following:
Table[x[i,j] = f[i,j], {i,1,10},{j,1,10}];
I want to set variables x[i,j] to have value ...
- 20.4k
1
vote
1
answer
74
views
Default Options not working in user-defined function for SymbolName
Abstract I have a function objectName[symbol] that returns the SymbolName as both a standalone function or when nested inside ...
- 1,647
1
vote
1
answer
109
views
Setting a function equal to another function then Clearing the latter
I have a loop in which several values of a function are computed, depending on the values for that function that were computed in the previous iteration of the loop. This could be implemented ...
- 1,375
1
vote
1
answer
97
views
Set: in part assignment is not a symbol [closed]
This is probably a basic question but I am new to Mathematica, so please help me out here.
I have the following piece of code:
...
- 125
2
votes
2
answers
56
views
Cannot understand meaning of "identical"
This came up in the context of plotting solutions to NDSolve, but I've reduced it to the following issue. This really has me scratching my head.
...
- 401
4
votes
2
answers
112
views
Using pure functions to assign a value to variable depending on whether it has been defined already
Let's say I want to assign to a variable the value $2020$ if it has not already been defined and do nothing if it has. In short, for a variable $a$, I want to achieve the functionality of ...
- 471
6
votes
4
answers
251
views
Assigning a string to variables names
I have the list
n1 = {{REL1, "REL.csv"}, {RAND1, "RAND.csv\"}}.
That is {{variable name, string}, {name, string}}. I want ...
- 125
2
votes
1
answer
46
views
Problem with superscript
I would like to know if there is option to make such scrpits like in this picture below.
Is option to put letter instead of a *?
- 25
4
votes
1
answer
122
views
Why the difference in performance? Array vs List and `Delete` vs `Nothing`
In a previous question I was warned against the use of Nothing to delete elements from a list, and rather use Delete. Being of ...
- 154
7
votes
1
answer
109
views
How would you explain Nothing[] weirdness? [duplicate]
I would like to use Nothing[] to make some elements of a list invisible. (The intended use is to remove a few unwanted points from a ...
- 154
9
votes
1
answer
132
views
Why Optional in Set is not held by the HoldFirst attribute?
When evaluatingf[x_:x0] := x, x0 will be evaluated, regardless of the HoldAll attribute of <...
- 702
4
votes
2
answers
226
views
Using module to define a function that calls another function: Should i use set-delayed (:=) or set (=)
Suppose that I have a function
f[x_,y_,z_]=x*y*z
and now suppose I want to consider a specific application where z is a ...
- 707