Questions tagged [conditional]
Questions about programming or mathematical constructs that enable verification, selection, or branching behavior when one or more criteria are determined to be True.
529
questions
1
vote
1
answer
56
views
Applying a condition to a column in a table using If
Let's assume we have the code below (The below code is derived from answer @DanielHuber link and answer @Domen link)
...
- 1,014
2
votes
1
answer
62
views
Why do logical operators not work in conditionals? [closed]
I am an absolute beginner, so it is possible that I've missed this--but in my exploration, logical operators like And, Or, ...
- 21
0
votes
1
answer
46
views
Integrate diverges for convergent integral, and returns unnecessary condition
I'm trying to solve an infinite integral using Mathematica. For some reason, Mathematica claims the integral diverges although when solving to a finite limit L and ...
- 433
0
votes
1
answer
64
views
Generate a three-dimensional table with data that satisfy a certain relation between them
I need to generate a 3 dimensional table of two variables x1 and x2 such that for any point x1, x2 must be smaller than x1^2+a^2, where a is some given constant. Something like the following ...
- 13
2
votes
0
answers
47
views
LaTeX symbols inside Expectation [duplicate]
I use LaTeX in my Mathematica code (using "^+4"), and was surprised that the first line in the code below evaluates correctly, but the second (essentially identical) line does not:
...
- 21
1
vote
1
answer
80
views
All possible tuples satisfying conditions
Let $\beta = (\beta_1, \beta_2, \ldots)$ be any given sequence of non-negative integers with all but finitely many $\beta_i$ zero. I want to collect all possible tuples $\beta^{\prime}= (\beta_1^{\...
0
votes
2
answers
86
views
NExpectation with complex condition
When I run a computation for NExpectation with a condition of the following form -- T>R>P -- the computation runs fine. But when I add another inequality -- T>R>P>S -- it gives me an '...
5
votes
3
answers
157
views
Evaluation control of nested With, If and Integrate
Can you explain the behaviour of the following?
The first With outputs unevaluated If.
So in the second ...
- 187
5
votes
1
answer
224
views
Which NDSolve method is most effective for the given chaotic system?
Note: This question is for those chaotic systems where the order of maximal Lyapunov exponent is around $10^{-3}$. So it's different from normal chaotic systems like Hénon–Heiles system, Yang-Mills-...
- 2,553
0
votes
1
answer
69
views
Which of the given codes $p1,p2,p3,p4$ is the correct one for imposing assumption in ContourPlot3D using RegionFunction?
I am using ContourPlot3D for the condition f[x_, y_, z_] ==0 assuming that the assumption ...
- 63
0
votes
1
answer
73
views
Using conditionals for a given function in Mathematica [closed]
I have two versions of a function (A and B)
When A fails, I get ...
- 21
5
votes
3
answers
226
views
How to highlight top N elements in each table column?
I have tables with column and row headings, similar to this one:
table = {{"",0.1,0.01},
{{1,0},1,3},
{{1,1},2,4}}
I want to highlight top N elements in ...
- 215
0
votes
1
answer
81
views
How to plot the given functions $g$ and $h$ with the assumption $f=0$?
I have a constraint f[a_, b_, c_] ==0 with three parameters $0<a,b,c<3$ where
...
- 749
0
votes
1
answer
112
views
Problem with If statement
It is a very simple problem but I am confused. A comment is required.
I have the following list
...
- 377
0
votes
0
answers
40
views
Trouble implementing switching hybrid system with NDSolve
I'm trying to use NDSolve to simulate a hybrid nonlinear system that switches between different linear behaviors based on states and inputs (i.e. switching from one linear behavior to another) which ...
3
votes
1
answer
147
views
Pattern matching vs. condition in a function
I'm trying to learn stuff from pattern matching but I found sometimes pattern matching does not work as I expected. Could anyone explain why the below outputs are not same? Thank you.
And could anyone ...
- 31
0
votes
0
answers
33
views
How to find clear solution for iterative problem by condition $<v_k ,v_n>=0$ If $k!=n$
I want to find x[n] by v[n] values without x[n] in solution by iterative below problem:
<...
- 83
0
votes
1
answer
78
views
A simpler way of identifying which elements of Tuples[{0,1,2,3},6] multiply with each of my codewords to give zero?
So I have a list of codewords. The codewords have length 64, so there are 64 codewords in my code. My code is over an alphabet of 4 (the code can be thought of as having four elements $0,1,2,3$ and ...
- 673
0
votes
1
answer
59
views
Creating an If function for the probabilities of the classes of images after using NetTrain
So I have 3 Classes the model can output after veiwing an image, at the moment it has a 70% accuracy, however this is not an issue as the plan is unless it's 85%+ sure on the Probability of the class ...
4
votes
4
answers
161
views
How to check if at least one ordering of the given row matches one of the rows of a table?
Consider some list of elements
...
- 5,921
3
votes
5
answers
242
views
How to check if the given row matches one of the rows of a table?
Consider some table
tabb = RandomInteger[{0, 4}, {5, 4}]
and a row
row = RandomInteger[{0, 4}, 4]
How to check if ...
- 5,921
1
vote
2
answers
102
views
Can you recover the original vectors that, when summed together, achieved a particular criteria
I am wondering if it is possible to take the binary strings of length $3$ (tuples) whose sums have weight $2$ (i.e they have $2$ non-zero entries)(binary case, meaning they have two $1$'s entries) $$u ...
- 673
0
votes
0
answers
52
views
Identify a condition among variables that satisfy an inequality
I have a symbolic function that produces the output
a = (1 - e - mu/n) Log[(1 - e - mu/n)/(1 - mu/n)] + (e + mu/n) Log[((e + mu/n) n)/mu]
If I substitute ...
- 496
4
votes
1
answer
340
views
Confused about If statement [closed]
I have this simple test code:
n1 = 0;
n2 = 0;
m = 0;
If[n1 == 0, n2 == 1]
which evaluates as False, as it should. However, if I do:
...
- 145
2
votes
3
answers
111
views
SetDelayed assignment not producing expected result when using ReplaceAll
In Mathematica, I am surprised that the following code does not do what I expect (what I expect is in comments after each evaluation). The problem seems to be due to the fact that when I define test ...
- 297
3
votes
1
answer
81
views
Adapt elements in the list, condition by condition
Could you give me some advice?
Suppose I have the following list.
box[1,1]={{4.4, {1,1}, {a}}, {1.5, {1,1}, {a}}, {10.8, {2,1}, {3a}}, {10, {1, 3}, {3a}}}
I want ...
- 446
1
vote
1
answer
59
views
Redundant cases from Sum
I am new to Mathematica. I would like to understand why Mathematica returns redundant cases, and whether it is possible to simplify them to the generic case $(n>1)$ that covers everything $(n\ge0)$....
- 111
3
votes
6
answers
705
views
Make a list of the first 100 primes, keeping only ones whose last digit is less than 3 [closed]
This is a question from an "Elementary Introduction to the Wolfram Language" Section 28: Tests and Conditionals. We are asked to "Make a list of the first 100 primes, keeping only ones ...
- 673
5
votes
1
answer
129
views
Condition inside pure function
Why condition /; not work inside pure function?
Suppose we have:
...
- 1,904
3
votes
1
answer
109
views
Compute the area of the union of the intersections of two conditions
I have four conditions over the two-dimensional domain $x,y\in[a,b]$. I want to use NIntegrate to compute the area of the union of the intersection of the two ...
- 349
0
votes
0
answers
41
views
Optimization of conditions applying
Let we have some data generator, e.g. lazy tuples or permutations.
I need to select data by some conditions cond1, cond2, …, up to 5-6 conditions.
All of them need ...
- 1,904
1
vote
2
answers
381
views
Parallelize a "For" cycle
I'm trying to parallelize a simple routine inside a "for" loop. Essentially, I need to compute the roots of a function $f(x)$ that depends on the discrete parameters $d$ and $R_0$. However, ...
- 491
1
vote
2
answers
61
views
Weird behavior of Which with lists [closed]
To demonstrate my problem, let's create a little function:
...
- 2,396
6
votes
1
answer
144
views
0
votes
3
answers
63
views
Efficient and compact replacement for Association in the following case
Consider the following association:
...
- 5,921
0
votes
2
answers
78
views
How to minimize computational time in an if condition?
I have a code as below:
...
4
votes
2
answers
340
views
Why does Select not work here?
Why does this not work? It returns empty while I expect the first two elements are selected.
...
- 723
6
votes
2
answers
177
views
Generate all adjacency matrices of size $n=4$ s.t. $a_{ij}\neq a_{ij}$ and $a_{ii}==0$
I want to generate a list of adjacency matrices of size $n=4$ s.t.
The diagonal is zero: $a_{ii}=0$ for all $i\in\lbrace 1,2,...,n\rbrace$
There are no 2-cyles, i.e. if $a_{ij}==1$, then $a_{ji}==0$ ...
- 91
4
votes
2
answers
118
views
How to discard the repeating elements of a list [closed]
Lets say there is a random list of expressions :
a={Sin[x], Sin[3 x], Sin[4 x], Sin[x], Sin[4 x], Sin[x], Sin [5 x], Sin[3 x], Sin[5 x]}
Plot[{a}, {x, 0, 2 Pi}]
...
- 867
1
vote
0
answers
90
views
0
votes
2
answers
129
views
Selecting the specific values from a table and saving in a table:
I have the following code:
...
- 867
0
votes
0
answers
49
views
Preventing Evaluation of Body of Manipulate
Overall, I am looking for a way to prevent the evaluation of the body of Manipulate until the controls meet a certain condition.
For example, consider the following....
- 1,627
2
votes
0
answers
131
views
The fastest and most scalable way to write a nested loop
The problem is to find the weights {w1,w2,w3,w4} that satisfy the condition. Which is the fastest and most scalable way (e.g. for 10000 weights) to write this ...
- 35
6
votes
7
answers
395
views
How to select elements from a list of pairs based on first element belonging to a different list?
This is my very first question and I really appreciate this ability and thankful the community.
I have two lists and need to select only those pairs from the first list, first element of which is ...
- 117
0
votes
1
answer
100
views
Is there any alternative for conditional plot that gives a more precise result in a shorter time?
I have the given function $Func$ and want to have a plot of those domains where $-3\leq Func\leq 3$ in precise details. I am using ...
- 361
1
vote
1
answer
161
views
How to plot multiple functions with conditions that assign values of some of them to be greater than the others?
i am trying to plot multiple functions in mathematica but i would like to do this in such a way that the values of two of my functions are always greater than the other two.
my functions are:
...
2
votes
2
answers
87
views
How to speedup comparison in the following example?
I have the following problem: I would like to generate random values of some variable $z$ obeying some distribution, but simultaneously within the interval zmin<...
- 5,921
4
votes
4
answers
190
views
Creating a cycle with conditions
I would like to arrange a gift exchange between 5 people, Alice, Bob, Carl, Danny, and Ellen, and I would like the gifts to be passed in a randomly created cycle (B->C->A->D->E->B), for ...
- 802
2
votes
2
answers
193
views
Removing "spikes" in data
Imagine I have a data set which gives me the following ListLinePlot
Is it possible to define a function over the data set that removes the "spikes" ...
- 4,933
0
votes
1
answer
139
views
Check the existence of roots based on parameters
I have a function which has one variable $r$ and two parameters $M,\lambda$. Whether or not the function has roots, depend on the parameters $M,\lambda$. I want to obtain a parameter space such that ...
- 83