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.
523
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Nested If question
Using the following code, I got the first two piecewise equations right but the third one returns -99.
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How to implement If criteria for the NestList-Function
I have a function which bisects a list in two parts recursively. Unfortunately I have to select a number of iterations for the NesList-function which is just an ...
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2
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Check an input matrix M contains any nonzero diagonal matrix element or not
Is there a way to easily check an input matrix M contains any nonzero diagonal matrix element or not?
For example,
if the M contains any nonzero diagonal matrix element, Output: True.
if the M ...
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vote
1
answer
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Find interval/range of certain coefficients to prove conditions of eigenvalues
I have seen similar questions to the one I am posting here, but I haven't been able to execute it on Mathematica. I would request some help with the following:
I have the following matrix:
...
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vote
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answer
98
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Proving conditions on absolute value of roots of a 5-degree polynomial
**I just need to find conditions on Subscript[[CapitalPhi], [Pi]] such that the fifth root of the polynomial is greater than 1 in absolute value. **
I have a 5-degree characteristic polynomial, for ...
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An anonymous function with constraints [duplicate]
I'm not very good at working with anonymous functions, a fact that has now come back to bite me. Suppose I have a function defined as follows:
...
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2
answers
195
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Find the range of a univariate function over a specific interval of the variable
I would like to find the range of the function below, but only for values of $a$ strictly greater than zero.
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234
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Restrict the domain of a function (and plot) it) when it depends on the value of a parameter [closed]
I know similar questions have been asked, but I am very new at Mathematica and other questions/answers are quite complex and do not suit the code I want to write.
I want to restrict the domain of the ...
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NMinimize over a list of integers
I'd like to minimize some function (of 3-4 variables) over a big list of integers, but not consecutive. Like arr = {5, 10, 7, 101,...}
I did not understand this ...
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How to make these lines smooth when using ContourPlot inside of a region?
Consider a region in the $(R,T)$ plane defined by the conditions $$0 < R\leq \pi,\quad |T|+R<\pi\tag{1}$$
Define $t(R,T)$ to be $$t(R,T)=\dfrac{1}{2}\left(\tan\left(\dfrac{T-R}{2}\right)+\tan\...
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How to symbolically evaluate expression within If[]?
I have a function, say f, that needs to take one of two symbolic forms depending on the value of its inputs. This function is part of a very large expression, and I'...
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Manipulate, IF statements, and displaying plots
When using manipulate and plotting a function within an IF statement, curly brackets appear in the panle with the displayed plot. Here is a simple version of the issue. Can someone tell how to ...
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How can I add conditions to simplify the result?
Here k is an integer number. How can I simplify the result by adding conditions like k is odd or even?
Also why are the 0^k terms not simplified to 0?
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How to use condition that adjacent elements are not acceptable for iterations
I'm trying to figure out how to create a matrix in mathematica, since I'm just starting working with the program to get a feel before I start graduate school. I'm working through a book problem where ...
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Plot part of a contour curve of the imaginary part of a complex function
I want to plot some contour cuvres of a simple function $f(z)=((z + 1/z)^2 - 4)*(1 - I)$.
The code ComplexContourPlot[Im[((z + 1/z)^2 - 4)*(1 - I)] == 0, {z, 2}] ...
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Replacements: using condition to restrict to parts that satisfy a Boolean expression
I need to replace all integers k in a list with {k} and tried:
EDITED: as a clarification: I mean all integer elements of a list, not all integers in the list, so in the following example, only 4 ...
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Manipulating lists based on conditionals and 3D plotting the smooth surface that bounds a list of points
First of all I want to create a list of evenly spaceed points in a cubic region in $\mathbb{R}^3$. Then I want to keep the points in this list which satisfy a certain condition, i.e. a function that ...
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Conditional tab view
I'd like to create a tabview with conditions on it, rather than put the tabview inside an If statement, to reduce the length of my code. i.e.
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Using If to Plot functions with specified parameters [closed]
Here's the question:
Plot f1(x) between x = -10 and x = +10, where f1(x) = +x2 when x is positive, f1(x) = -50 when x is -2 or smaller, and f1(x) = 0 otherwise
I'm new to using Mathematica and the If ...
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How do I use If to plot a function conditionally
I am trying to use the If so that when the 1st argument is true, it plots a graph of a function and when false, returns 0. I know that the format of an if statement ...
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If condition in differential equation
I need to plot the Integrate the Fire model of neuron. The differential equation is $\frac{dV}{dt} + \frac{V}{\tau} = \frac{I}{C}$. The initial condition is $V(0) = 0$. And there is this condition if ...
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How to abort evaluation when clicking CancelButton in program with Dialog boxes?
If you run the following code you will notice when Cancelbutton is clicked, the output is an $Abort, but it continues running the following cells, I tried different things but no one works.
I want to ...
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How to plot zeros of a function as a thin stripe?
I have this function for $0<x<20$
f[x_] := Cos[x] + 2 Cos[2 x];
and I want to graphically represent the points where this function is zero, as a thin line ...
user76607
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How to use plot [ If ] to show the points where $\sin x=0$? the code is given
I am using this code to get a result showing the points $x$ for which $\sin x=0$ as a thin stripe at $y=5$. But the plot I get is empty. I wonder if someone explains please what is wrong with this ...
user76607
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534
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Continue[ ] command will not work within If statement [closed]
I am currently using the Module command for dynamical programming.
Within the Module, I have an If statement
...
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81
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Getting ParametricNDSolveValue::mxst: [closed]
I'm trying to create a manipulatable SIR model with variable infection rate in Mathematica. To (very roughly) imitate the effect of government policies, I want the infection rate to be a certain ...
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68
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function changes upon condition
I have the function
f[x_,y_]:=1/(Sin[x]+Sin[y])
which obviously becomes infinite for $x=\pi n, \;y=\pi n$ where $n\,\epsilon \, \mathbf{N}$.
I want to give ...
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47
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When I insert an if block into the ScheduledTask, I'm entering the password and the program is closing
I'm new in Mathematica. So I'm unable to settle a matter. When I insert an if block into the ScheduledTask, I'm entering the password and the program is closing. What is my mistake? Can you help me ...
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How can I create a randomHop function that would return certain coordinates? [closed]
I've tried to create a function that's equal to a loop containing 4 if functions, one for each integer, but the result would not show the desired outcome. How can I go about doing this question?
Write ...
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Need help with using nested If expressions in NDSolve
Questions regarding the use of nested For-loops have been posted a few times on StackExchange. However, I think that the solutions to those questions are not really applicable to what I am trying to ...
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Checking for discontinuities
There was an older post about checking the continuity of a function but the routines in the reply don't seem to work for my function. Hence the new post.
If I have a function
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119
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Expectation with conditional random variable [closed]
Given an Exponentially Distributed Random Variable $X\sim \exp(1)$, I need to find $\mathbb{E}[P_v]$ in Mathematica, where $P_v$ is given as:
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Add condition for not plotting in some cases
I have the following function. Now I want to add condition to not plot when the function is ComplexInfinity, Indeterminate, or <...
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"If" not working when solving piecewise differential equation
This is a part 2 to my previous question:
Solving Piecewise Differential Equation
I am embarking on a physics project and this is the simulation that I would like to do. More information is included ...
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218
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Solving Piecewise Differential Equation
I am trying to simulate something using differential equations. However, the equations are piecewise.
Here is my code:
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369
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If statement doesn't work properly [closed]
As the image shows, If doesn't return "Fail" if the condition didn't succeed, but works when conditions match. Why did that happen and how can I fix it?
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1
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47
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Using For to generate a sequence
I want to find the smallest positive integer $k$ such that the finite list s[k*m] contains no odd numbers, for $m=1,2 \dots$. Unfortunately ...
0
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1
answer
87
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Allowing choice between If statements in user-friendly way
Is there a user-friendly way to get a Mathematica notebook to choose between If statements according to the value of a variable?
I would like the user to be able to ...
user59886
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If statement in dynamic cluster query
I use a High-Performance Cluster for some of my work. I can dynamically see the state of the work but I couldn't use the If statement in the cluster query. I want to hear a sound when my work finishes....
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2
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Use Mathematica to split a sequence according to other two sequences
I want to use Mathematica to solve the following problem:
For example I have a sequence 101. I want to compare it with $1101$ and $0101$. The comparison has the following procedure:
Check the first ...
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Usage of 'Less than' condition in Sum
I have following sum: $$ \sum_{\substack{n,j\\j<n}}^{3} x_nx_j$$. How can I give this $j<n$ condition in Sum?
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How to check if solution to NSolve exists?
I'm trying to created a table where the entries are values of x, either given by x/.NSolve[...][[1]] or a fixed value x0 if there is no numerical solution. Is there a way to find the truth value for ...
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NIntegrate with a function defined with conditions
Good afternoon,
I am trying to integrate a function that is defined with a conditional. The simplified code is the following:
...
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How do I extract the minima from a list of NMinimize outputs in a smart way?
I am trying to find the absolute minimum of a potential surface on the x-y plane as a function of a third parameter p which changes the shape of this surface. In other words: at p=1, I want the ...
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How to find random values of variable satisfying multiple conditions?
I have multiple conditions to be satisfied
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49
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Seamless ContourPlot for a conditional function
When I try to create a ContourPlot of a continuous conditional function, Mathematica leaves a "seam" in between the two regions demarcated by the conditional. How do I fill this seam?
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251
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Constant inside If condition
I hope you are doing well.
I am currently writing some code in which I have an If statement where I will be dividing two expressions and checking to see if the quotient comes out to be a constant ...
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Obtain fairly sampled data set subject to a condition?
I need to obtain a random distribution of some parameters {t1,t2,t3} subject to a set of conditions. For example,
...
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Can't make this "If" clause work
I am writing a code that creates a population with a probability to die for each citizen. They all start with some age, and after each application of the function, it either kills a person or adds +1 ...