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Questions tagged [piecewise]

"piecewise" may refer to a piecewise function, a piecewise interpolation or a piecewise regression / smoothing.

Defining a piecewise function normally requires writing if ... else ... clause.

Interpolation is inherently piecewise.

Piecewise regression often refers to piecewise linear regression, or segmented regression.

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How to apply piecewise linear fit in Python?

I am trying to fit piecewise linear fit as shown in fig.1 for a data set This figure was obtained by setting on the lines. I attempted to apply a piecewise linear fit using the code: from scipy import optimize import matplotlib.pyplot as plt import…
Tom Kurushingal
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C++11 use-case for piecewise_construct of pair and tuple?

In N3059 I found the description of piecewise construction of pairs (and tuples) (and it is in the new Standard). But I can not see when I should use it. I found discussions about emplace and non-copyable entities, but when I tried it out, I could…
towi
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Why is there no piecewise tuple construction?

The standard templates std::pair and std::array are special cases of std::tuple, and it stands to reason that they should have a very similar set of capabilities. However, uniquely among the three, std::pair allows for piecewise construction. That…
Kerrek SB
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Piecewise regression with R: plotting the segments

I have 54 points. They represent offer and demand for products. I would like to show there is a break point in the offer. First, I sort the x-axis (offer) and remove the values that appears twice. I have 47 values, but I remove the first and last…
Antonin
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Constructing piecewise symbolic function in Matlab

I am trying to generate a piecewise symbolic function in Matlab. The reason it has to be symbolic is I want to be able to integrate/differentiate the function afterwards and/or insert actual values. I have the following function: x^3/6 -> 0 < x…
Maximilian Csuk
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Define Piecewise Functions in Julia

I have an application in which I need to define a piecewise function, IE, f(x) = g(x) for [x in some range], f(x)=h(x) for [x in some other range], ... etc. Is there a nice way to do this in Julia? I'd rather not use if-else because it seems that…
user3587051
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Extrapolate from triangulation

Suppose we have five vertices: X = [0 1; 2 1; 4 1; 1 0; 3 0]; a triangulation: T = [1 4 2; 4 5 2; 5 3 2]; and function values defined on the vertices: Fx = [1; 2; 3; 4; -5]; then we can easily…
Paul
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Piecewise linear fit with n breakpoints

I have used some code found in the question How to apply piecewise linear fit in Python?, to perform segmented linear approximation with a single breakpoint. The code is as follows: from scipy import optimize import matplotlib.pyplot as plt import…
Erlend Vollset
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Multiple Pieces in a numpy.piecewise

I am taking a course on Fuzzy Systems and I take my notes on my computer. This means that I have to draw graphs on my computer from time to time. Since these graphs are quite well defined, I feel that plotting them with numpy would be a good idea (I…
inspectorG4dget
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how to specify a range in numpy.piecewise (2 conditions per range)

I am trying to construct a piecewise function for some digital signal processing, but I cannot get numpy.piecewise to allow me to specify a range. Here is what I want to input: t = np.arange(-10,10,1) x = lambda x: x**3 fx = np.piecewise(t, [t < -1…
Pswiss87
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How can I create a piecewise inline function in MATLAB?

I have a function in MATLAB which takes another function as an argument. I would like to somehow define a piecewise inline function that can be passed in. Is this somehow possible in MATLAB? Edit: The function I would like to represent is: f(x) = {…
Scott
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piecewise function fitting with nls() in R

I am trying to fit a two-part line to data. Here's some sample data: x<-c(0.00101959664756622, 0.001929220749155, 0.00165657261751726, 0.00182514724375389, 0.00161532360585458, 0.00126991061099209, 0.00149545009309177, 0.000816386510029308,…
FGiorlando
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How to define a piecewise function in R

I want to define a piecewise function using R, however, my R code goes wrong. Any suggestion is welcome. x<-seq(-5, 5, by=0.01) for (x in -5:5){ if (-0.326 < x < 0.652) fx<- 0.632 else if (-1.793
Frank Wang
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how to generate a random convex piecewise-linear function

I want to generate a toy example to illustrate a convex piecewise linear function in python, but I couldn't figure out the best way to do this. What I want to do is to indicate the number of lines and generate the function randomly. A convex…
belcansi
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How to use ggplot2 to plot results from 'segmented' package?

I followed these steps to plot the results of a piecewise linear regression with one breakpoint which I have done by segmented package: lin.mod <- lm(ChH~CL) segmented.mod <- segmented(lin.mod, seg.Z=~CL) data1 <- data.frame(x = CL, y = ChH) data2…
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