Calculates a 'Fourier elliptical shape' given Fourier coefficients
Usage
efourier_shape(
an = NULL,
bn = NULL,
cn = NULL,
dn = NULL,
n = 1,
nharm = NULL,
npoints = 150,
alpha = 4,
plot = TRUE
)
Arguments
- an
The an Fourier coefficients on which to calculate a shape.
- bn
The bn Fourier coefficients on which to calculate a shape.
- cn
The cn Fourier coefficients on which to calculate a shape.
- dn
The dn Fourier coefficients on which to calculate a shape.
- n
The number of shapes to generate. Defaults to 1. If more than one shape is used, a list of coordinates is returned.
- nharm
The number of harmonics to use. It must be less than or equal to the length of
*_n
coefficients.- npoints
The number of points to calculate.
- alpha
The power coefficient associated with the (usually decreasing) amplitude of the Fourier coefficients.
- plot
Logical indicating Whether to plot the shape. Defaults to ´TRUE`
Details
efourier_shape
can be used by specifying nharm
and
alpha
. The coefficients are then sampled in an uniform distribution
(−π;π) and this amplitude is then divided by harmonicrankalpha. If alpha
is lower than 1, consecutive coefficients will thus
increase. See Claude (2008) pp.223 for the maths behind inverse ellipitical
Fourier
Adapted from Claude (2008). pp. 223.