Range of data with BezierFunction
- To: mathgroup at smc.vnet.net
- Subject: [mg112498] Range of data with BezierFunction
- From: Viktor Korbel <v.korbel at gmail.com>
- Date: Fri, 17 Sep 2010 06:43:07 -0400 (EDT)
According to the information about the BezierFunction, the parameters
u, v, =85 by default run from 0 to 1 over the domain of the curve or
other manifold.
I'm wondering if there is a way to change this range so to reflect the
range of original data fitted by the BezierFunction.
Example:
In: datalist = {{0, 1}, {1, 2}, {2, 1}, {3, 4}, {4, 5}};
In: bfunc = BezierFunction[datalist]
Out: BezierFunction[{{0.,1.}},<>]
At this point I can only use a value between 0 and 1 to evaluate bfunc:
In: bfunc[.2]
to extract the x and y values:
Out: {0.8, 1.4928}
If I want to have the value of bfunc when x is, for instance, 4, I'm
forced to perform additional calculations.
Additional problems arise if I want to calculate the derivative of bfunc:
In: bfunc'[.2]
Out: {4., 1.696}
The x value corresponds now always to the highest x value.
The solution would be to force BezierFunction to use the original
range of data. Is this possible?
Viktor