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Jan
19
comment Is there a standard way to obtain an approximation piecewise-linear function for a function
Yes but its not what I want. I want a piecewise linear function, represented by a set of points.
Jan
19
comment Is there a standard way to obtain an approximation piecewise-linear function for a function
@njuffa Not sure what's unclear. If I have a function $f(x)$ I want a vector of pairs $(<x_0, f(x_0)>, <x_1, f(x_1)>, ... )$ that represent a piecewise-linear approximation of the curve of $f(x)$. I do not know $x_0, x_1 ... $ for each function, so discovering them is part of the algorithm I am looking for, and they will be specific for each specific function, and not at regular intervals. I do not want a polynomial approximation though, just a piecewise-linear one.
Jan
18
comment Is there a standard way to obtain an approximation piecewise-linear function for a function
Fair enough, changed to $g(x)$ :). Any idea how do I go about this, or from where do I start looking?
Jan
18
revised Is there a standard way to obtain an approximation piecewise-linear function for a function
deleted 1 character in body
Jan
18
asked Is there a standard way to obtain an approximation piecewise-linear function for a function
Dec
20
awarded  Caucus
Dec
20
accepted Computing the value of a function whose derivative is another function
Dec
19
comment Computing the value of a function whose derivative is another function
Cheers. So if $g(t)$ itself is also a function dependent on $h(t)$, I should start at the bottom, integrate each, until I arrive to the integral of $g(t)$. Am I on the right track?
Dec
19
comment Computing the value of a function whose derivative is another function
@KSmarts Well I might need to compute $g(t)$ depending on some other function, but in the simplest case they will all boil down to a constant rate linear function.
Dec
19
comment Computing the value of a function whose derivative is another function
@AndrewSalmon By dependent variables I meant the functions on which $f(t)$ depends on. For example the state of charge of a battery depends on time spent charging and the temperature, but temperature also changes according to time.
Dec
19
asked Computing the value of a function whose derivative is another function
Jul
2
awarded  Curious
May
10
accepted Biasing sigmoid curve
May
2
comment Biasing sigmoid curve
Lets say 'c = 10', which is where I want $y$ to be almost $0$. I was imagining the S shape to skew a little upwards such that $f(5) > 0.5$ (for fit values). But I guess your approach is good too. It still promotes fit values a bit more than the average, and unfit less.
May
1
comment Biasing sigmoid curve
The power approach seems to squash the sigmoid to the left if $a > 1$, and stretch it to the right if $a < 1$. I was thinking more on the lines of changing the S shape such that its skewed upwards, however your idea might have a good effect too. +1
May
1
revised Biasing sigmoid curve
added 3 characters in body
May
1
asked Biasing sigmoid curve
Feb
6
comment Math notation for summing up the rows in a matrix
Thanks. Seems that this is the 'standard' way then...
Dec
1
awarded  Tumbleweed
Nov
21
accepted Function with a continuous domain but a discrete range