topinquad grid manipulation
Return value
a n element vector. Where n is the number of elements of
x. res[i]=j means that the point number i is located in the
quadrilateral number j with (0 <= j <= n_elements(x0)-1)
Parameters
x
in
required
y
in
required
x1
in
required
y1
in
required
x2
in
required
y2
in
required
x3
in
required
y3
in
required
x4
in
required
y4
in
required
Keywords
ONSPHERE
DOUBLE
ZOOMRADIUS
NOPRINT
NEWCOORD
Examples
IDL> res = inquad(x, y, x1, y1, x2, y2, x3, y3, x4, y4)
IDL> x = 1.*[1, 2, 6, 7, 3]
IDL> y = 1.*[1, 3, 3, 4, 7]
IDL> x1 = 1.*[0,4,2]
IDL> y1 = 1.*[1,4,8]
IDL> x2 = 1.*[1,6,4]
IDL> y2 = 1.*[5,6,8]
IDL> x3 = 1.*[3,8,4]
IDL> y3 = 1.*[4,4,6]
IDL> x4 = 1.*[2,6,2]
IDL> y4 = 1.*[0,2,6]
IDL> splot, [0,10], [0,10], xstyle = 1, ystyle = 1,/nodata
IDL> for i=0,2 do oplot, [x4[i],x1[i],x2[i],x3[i],x4[i]],[y4[i],y1[i],y2[i],y3[i],y4[i]]
IDL> oplot, x, y, color = 20, psym = 1, thick = 2
IDL> print, inquad(x, y, x1, y1, x2, y2, x3, y3, x4, y4)
On a sphere see clickincell.pro...
Version history
Version
$Id$
History
Sebastien Masson (smasson@lodyc.jussieu.fr)
August 2003
Based on Convert_clic_ij.pro written by Gurvan Madec
Known issues
Restrictions
I think degenerated quadrilateral (e.g. flat of
twisted) is not work. This has to be tested.