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0answers
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1
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0answers
50 views

Maximize and NMaximize don't work for my function

I defined the following function: d1[x_] := Min[Abs[FractionalPart[x]], 1 - Abs[FractionalPart[x]]] and tried to evaluate the following function: ...
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votes
1answer
29 views

Cannot determine, what this partw error message is aiming at …

So i am trying to plot the magnetic vector field surrounding a "flat conducting cable" (don't know the proper english expression). This is the "code" (there are some constants in the analytic ...
0
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1answer
60 views

How I can make the StreamPlot of this differential equation?

I need the StreamPlot of this differential equation but I don't know how. dp/dt=0.4p(1 - p/30), 0 <= t < 5 and 0.4p(1 - p/30) - 0.25p, t > 5
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3answers
75 views

Fill an array, symmetric with respect to its centre

I want to create an array that must be symmetric with respect to the centre of it, as in the following example: 0 1 2 3 4 3 2 1 but, instead of having such ...
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0answers
25 views

Filling Piecewise Function leaves gaps [duplicate]

When I use the fill feature to shade the area between the curve and the x-axis, there is no fill when x=2. I don't understand how this is possible since the function is defined there. Any help to fill ...
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0answers
46 views

How to make Piecewise continuous [duplicate]

I have a function defined by its slope in a continuous sequence of intervals, e.g. ...
1
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1answer
75 views

How to draw dots at beginning and end of range when plotting [duplicate]

I'm trying to plot a Piecewise function which should look like this: How can I have similiar dots (filled or empty) at beginning and end of range? ...
0
votes
2answers
95 views

Using parts of piecewise function

I define: f[x_] := Piecewise[{{5, 0 <= x < 10}, {g[x], 10 <= x < 15}, {h[x], x > 15}}] Then I try to solve ODE: ...
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1answer
73 views

Piecewise ColorFunction for Plot3D

I want to make a 3D plot where the ColorFunction is different depending on whether the function value is positive or negative. I know how to do the following: ...
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2answers
124 views

Convolution of a piecewise function

I want to find the convolute the the functions in the Convolve command ...
1
vote
1answer
52 views

Piecewise function and integral function

Given a piecewise function f[t_]:=Piecewise[{{Exp[-1/t^2],t>0},{0,x<=0}}], I can define another function like this: ...
3
votes
1answer
71 views

How to make the result of Piecewise be a closed interval?

Description This question comes from two questions. Namely Q1 and Q2 The defintion of B-Spline basis function as shown below: Let $\vec{U}=\{u_0,u_1,\ldots,u_m\}$ a nondecreasing sequence of real ...
2
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2answers
156 views

Plotting boundary of piecewise function in ContourPlot

I am trying to do a ContourPlot of the following function: ...
5
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4answers
301 views

Plotting piecewise functions

I have a list of N functions called functionList. N can be any number. Also, I have a list ...
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1answer
56 views

Integral for piecewise function inconsistent with the usual way

I have the following piecewise function: ...
1
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1answer
55 views

Sum of two Piecewise functions give wrong vector

I would like to calculate the normal at a certain point of a parabola. The parabola is defined only on a certain area according to a Piecewise function. Afterwards ...
4
votes
2answers
238 views

Solving a discontinuous differential-algebraic equation system for plasticity behaviour

I need to solve a discontinuous equation which is typical in theory of plasticity. For a simple case I get the following equation system (reformulated for numerical implementation): $s(t) = ...
1
vote
1answer
49 views

Using If statement for more than two cases [closed]

I want to use the If statement for three different scenario. Can someone help me out? Pls also indicate if there is a better function to do that. This is an example ...
2
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1answer
195 views

Piecewise smooth rectangle pulse

I am wondering how to create a single rectangle pulse with nonlinear riding and falling edges on both sides. I don't know whether it is better to do it piecewise or to mathematically transform the ...
0
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1answer
53 views

Finding a solution when there are two piecewise functions at play

The goal is to mathematically figure out where is the point when the both of the diagrams are the same distance to the Y-axis. The solution to such a problem can be obtain quite easily by just ...
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0answers
65 views

Piecewise functions Integration with symbol

I want to integrate one piecewise functions as following, ...
3
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1answer
342 views

Define and plot a piecewise function with parameters [closed]

I have this function , but i do not know how to define it in mathematica \begin{equation} f_t(x)=% \begin{cases} i& \text{$\frac{1}{1+i}<|x-t|\le \frac{1}{i}$} \\ ...
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0answers
47 views

Transform NMinimze into LinearProgramming formulation

I have the following maximization problem that I currently try to solve with Minimize/NMinimize. Unfortunately, this kind of solution method takes really long for large systems of equations and ...
4
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1answer
376 views

Integrate over piecewise function defined using /;

f[x_] := x /; x<0 f[x_] := x^2 /; x>=0 Integrate[f[x],{x,-1,1}] The above does not work (Mathematica returns it unevaluated), but the below does. ...
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vote
1answer
139 views

Understanding a piecewise function generated by Mathematica

After some simplifications I was eventually get the following piecewise function. ...
0
votes
1answer
121 views

PolarPlot works, ParametricPlot doesn't [closed]

Am new to Mathematica, so if this question has been asked already, apologies. Have a (polar) spline function and Mathematica did a fine job of calculating from my inputs and giving me the piecewise ...
2
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1answer
127 views

(Very) ill-behaved Piecewise Plot

I am interested in defining a function (with arguments: a symbol for a variable and a list of 6 points) that represents a quadratic interpolating spline of the points. Here is my attempt ...
2
votes
3answers
121 views

Why do plot functions fail to plot expressions containing piecewise functions? [closed]

Why do both of the following plots appear empty in Mathematica? I tried evaluating the functions $\chi_+$ and $\chi_-$ at various points and it seems valid, so why does Mathematica not plot them? ...
2
votes
1answer
72 views

Plotting a piecewise function with strange subdomains

I have a function, which analityc expression is $C=2*max[b-c,0]$(you can see the expressions of b and c down). Then I have to considerer $q_\pm=\frac{(1\pm \sqrt{ (1-C^2)})}{2}$ and then to plot ...
2
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0answers
55 views

Data paste in piecewise table

How can I paste data copied from several lines into a piecewise table, without pasting it in a single cell?
5
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3answers
534 views

Piecewise Polynomial Interpolation

Given some data pairs $(x_i,y_i)$, with $i=0,...,m$, and a degree $r$, I wish to build a piecewise polynomial function to interpolate these data. That interpolation should be continuous, and, on every ...
1
vote
2answers
298 views

Plotting 3D piecewise function with distinct colors

I want to draw the following picture in Mathematica as shown below with distinct color for each section.
1
vote
1answer
49 views

PiecewiseExpand doesn't take all kind of assumptions

Running PiecewiseExpand[expr, assum] does not work with all kind of assumptions. For example, the following line will not split the expression with absolute values in the chambers, considering m1=m2. ...
2
votes
1answer
126 views

Piecewise conditions with a parametric PDE

I'm using ParametricNDsolve to check best fit of a model (function Eb1) with some data, and I have four free parameters I want to test. I can easily construct a Parametric solution between the two ...
1
vote
2answers
539 views

3D Plotting with PieceWise function

Im trying to plot the following function: $f(x,y)$ = $\left\{\begin{matrix} (x+y) & (x,y) \in T \\ (x+y)^2 & (x,y) \notin T \end{matrix}\right.$ where $T= \{ y\leq -x+1, x\geq 0, y\geq ...
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2answers
431 views

How to plot this function?

I'd like to plot the function $f$ in this answer http://math.stackexchange.com/a/788818/66096 Let $h(x) = \begin{cases} e^{ -\frac{1}{1 - (1-2x)^2}} & \mbox{ for } 0<x < 1\\ 0 & ...
1
vote
1answer
72 views

Inaccuracy of Piecewise function? [duplicate]

I have the following issue and can't find a solution so far. ...
0
votes
1answer
82 views

Define function that goes from one point to another parametrically

I have two points p1 and p2, and I want to get the parametric equation of a linear function that passes through those, but ranging from one point to another. For example, if I have 2 points {0,0} and ...
0
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1answer
93 views

Definite Integral, Piecewise, Error

I am trying to evaluate the following: ...
3
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2answers
71 views

Mathematica: Extract the piece that contains x=0 from within a piecewise function

In mathematica, I have a piecewise function similar to: Piecewise[{ {x^2 + 2*x - 4, 0 <= x <= 1/4}, {0, true} }] I don't ...
4
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1answer
536 views

Fitting piecewise functions

I have several large data sets which follow the following pattern: A position is measured, a force is applied until a new equilibrium is found. I'd like to find a fit for the position, at least at the ...
0
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1answer
299 views

Manipulating a piecewise function

A while ago I posted a question regarding differential equations. It was supposed to model heat transfer. We've refined our model a bit (using numerical methods now). Our code now looks like this: ...
2
votes
2answers
494 views

Trying to solve a differential equation with a piecewise initial condition

I am trying to solve $$u_t=\frac{1}{4}u_{xx}$$ $-\infty<x<\infty,\: t>0$ With the initial condition $u(x,0)=\phi(x)$ where $$ \phi(x)= \left\{ \begin{array}{lr} 1 & ...
0
votes
1answer
252 views

Nonlinear fit with piecewise functions

I have an ensemble of data points $(x_i,y_i)$ and I need to fit them according to $y=F(a,b,x)$ if $x \leq x_{ref}$ and $y=G(c,d,x)$ if $x \geq x_{ref}$. The parameters I need to adjust are then ...
0
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2answers
250 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: ...
3
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4answers
485 views

How to build a funcion that returns a piecewise function

I dont know how to go ahead with this The problem statement is "Make a piecewise linear function maker that accepts lists of points as input and has a piecewise linear function as the output". Lets ...
5
votes
1answer
123 views

Define customised distribution with discontinuous CDF

I have the following CDF: ...
2
votes
1answer
458 views

Defining Piecewise Functions [duplicate]

I'm having trouble defining piecewise functions. What I have so far is a function that outputs something in a suitable format for Piecewise: ...
4
votes
3answers
299 views

Creating a function with integral zeroes of the 0th, 1st, and 2nd derivatives

I would like to be able to randomly generate functions, each of which satisfies $f : [-10, 10] \rightarrow [-10, 10]$ All the zeroes, critical points, and inflection points have an integral ...