GE | R Documentation |
GE
is used to calculate polar radii of the original Gielis equation
or one of its simplified versions at given polar angles.
GE(P, phi, m = 1, simpver = NULL, nval = 1)
P |
the parameters of the original Gielis equation or one of its simplified versions. |
phi |
the polar angle(s). |
m |
the given |
simpver |
an optional argument to use the simplified version of the original Gielis equation. |
nval |
the specified value for |
When simpver = NULL
, the original Gielis equation is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\frac{1}{k}\,\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{3}}\right)^{-\frac{1}{n_{1}}},
where r
represents the polar radius at the polar angle \varphi
;
m
determines the number of angles within [0, 2\pi)
; and a
, k
, n_{1}
,
n_{2}
, and n_{3}
need to be provided in P
.
\quad
When simpver = 1
, the simplified version 1 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}\right)^{-\frac{1}{n_{1}}},
where a
, n_{1}
, and n_{2}
need to be provided in P
.
\quad
When simpver = 2
, the simplified version 2 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}\right)^{-\frac{1}{n_{1}}},
where a
and n_{1}
need to be provided in P
, and n_{2}
should be specified in nval
.
\quad
When simpver = 3
, the simplified version 3 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}+
\left|\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}\right)^{-\frac{1}{n_{1}}},
where a
needs to be provided in P
, and n_{1}
should be specified in nval
.
\quad
When simpver = 4
, the simplified version 4 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}+
\left|\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}\right)^{-\frac{1}{n_{1}}},
where a
and n_{1}
need to be provided in P
.
\quad
When simpver = 5
, the simplified version 5 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{3}}\right)^{-\frac{1}{n_{1}}},
where a
, n_{1}
, n_{2}
, and n_{3}
need to be provided in P
.
\quad
When simpver = 6
, the simplified version 6 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\frac{1}{k}\,\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}\right)^{-\frac{1}{n_{1}}},
where a
, k
, n_{1}
, and n_{2}
need to be provided in P
.
\quad
When simpver = 7
, the simplified version 7 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}+
\left|\frac{1}{k}\,\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{2}}\right)^{-\frac{1}{n_{1}}},
where a
, k
, and n_{1}
need to be provided in P
, and n_{2}
should be specified in nval
.
\quad
When simpver = 8
, the simplified version 8 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}+
\left|\frac{1}{k}\,\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}\right)^{-\frac{1}{n_{1}}},
where a
and k
are parameters that need to be provided in P
, and n_{1}
should be specified in nval
.
\quad
When simpver = 9
, the simplified version 9 is selected:
r\left(\varphi\right) = a\left(\left|\mathrm{cos}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}+
\left|\frac{1}{k}\,\mathrm{sin}\left(\frac{m}{4}\varphi\right)\right|^{n_{1}}\right)^{-\frac{1}{n_{1}}},
where a
, k
, and n_{1}
need to be provided in P
.
The polar radii predicted by the original Gielis equation or one of its simplified versions.
simpver
here is different from that in the TGE
function.
Peijian Shi pjshi@njfu.edu.cn, Johan Gielis johan.gielis@uantwerpen.be, Brady K. Quinn Brady.Quinn@dfo-mpo.gc.ca.
Gielis, J. (2003) A generic geometric transformation that unifies a wide range of natural
and abstract shapes. American Journal of Botany 90, 333-
338. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.3732/ajb.90.3.333")}
Li, Y., Quinn, B.K., Gielis, J., Li, Y., Shi, P. (2022) Evidence that supertriangles exist in nature from the vertical projections of Koelreuteria paniculata fruit. Symmetry 14, 23. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.3390/sym14010023")}
Shi, P., Gielis, J., Quinn, B.K., Niklas, K.J., Ratkowsky, D.A., Schrader, J., Ruan, H.,
Wang, L., Niinemets, Ü. (2022) 'biogeom': An R package for simulating and fitting natural
shapes. Annals of the New York Academy of Sciences 1516, 123-
134. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1111/nyas.14862")}
Shi, P., Ratkowsky, D.A., Gielis, J. (2020) The generalized Gielis geometric equation and its application. Symmetry 12, 645. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.3390/sym12040645")}
Shi, P., Xu, Q., Sandhu, H.S., Gielis, J., Ding, Y., Li, H., Dong, X. (2015) Comparison
of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship
between spatial density of plants and total leaf area per plant. Ecology and Evolution 5,
4578-
4589. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1002/ece3.1728")}
areaGE
, curveGE
, DSGE
, fitGE
,
SurfaceAreaSGE
, TGE
, VolumeSGE
GE.par <- c(2, 1, 4, 6, 3)
varphi.vec <- seq(0, 2*pi, len=2000)
r.theor <- GE(P=GE.par, phi=varphi.vec, m=5)
dev.new()
plot( varphi.vec, r.theor, cex.lab=1.5, cex.axis=1.5,
xlab=expression(italic(varphi)), ylab=expression(italic("r")),
type="l", col=4 )
graphics.off()
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