1 | function numtri, index, nx, ny |
---|
2 | ; |
---|
3 | compile_opt idl2, strictarrsubs |
---|
4 | ; |
---|
5 | |
---|
6 | y=index/nx |
---|
7 | x=index-y*nx |
---|
8 | numtri = (y NE 0)*(nx-1)*(2*(y-1)+1) + (2-(y EQ (ny-1) OR y EQ (ny-1)))*x |
---|
9 | |
---|
10 | return, numtri |
---|
11 | end |
---|
12 | |
---|
13 | |
---|
14 | ;+ |
---|
15 | ; NAME:definetri |
---|
16 | ; |
---|
17 | ; PURPOSE:Define a triangulation array like TRIANGULATE but for a |
---|
18 | ; E-grid type |
---|
19 | ; |
---|
20 | ; CATEGORY: make contours with E-grid type |
---|
21 | ; |
---|
22 | ; CALLING SEQUENCE:triangles=definetri(nx, ny [,vertical]) |
---|
23 | ; |
---|
24 | ; INPUTS: nx and ny are the array dimensions |
---|
25 | ; |
---|
26 | ; OPTIONAL INPUTS: |
---|
27 | ; |
---|
28 | ; vertical: When vertical is undefine all rectangles are cut |
---|
29 | ; in using the horizontal diagonal. Vertical is a vector which |
---|
30 | ; contains the rectangles numbers which are cut in using the |
---|
31 | ; vertical diagonal. |
---|
32 | ; The rectangle number is define by the index (in a nx*ny |
---|
33 | ; vector) of the lower-left corner of the rectangle. |
---|
34 | ; |
---|
35 | ; KEYWORD PARAMETERS: |
---|
36 | ; |
---|
37 | ; OUTPUTS: |
---|
38 | ; triangles is a 2d array and is dimensions are 3 and |
---|
39 | ; 2*(nx-1)*(ny-1) |
---|
40 | ; triangles is define like in the TRIANGULATE procedure. |
---|
41 | ; |
---|
42 | ; |
---|
43 | ; OPTIONAL OUTPUTS: |
---|
44 | ; |
---|
45 | ; COMMON BLOCKS: |
---|
46 | ; |
---|
47 | ; SIDE EFFECTS: |
---|
48 | ; |
---|
49 | ; RESTRICTIONS: |
---|
50 | ; |
---|
51 | ; PROCEDURE: |
---|
52 | ; |
---|
53 | ; EXAMPLE: |
---|
54 | ; |
---|
55 | ; |
---|
56 | ; MODIFICATION HISTORY: sebastien Masson (smlod@ipsl.jussieu.fr) |
---|
57 | ; June 2001 |
---|
58 | ; |
---|
59 | ;- |
---|
60 | FUNCTION definetri_e, nx, ny, singular, SHIFTED = shifted |
---|
61 | ; |
---|
62 | compile_opt idl2, strictarrsubs |
---|
63 | ; |
---|
64 | nx = long(nx) |
---|
65 | ny = long(ny) |
---|
66 | triangles = lonarr(3, 2*(nx-1)*(ny-1)) |
---|
67 | ; |
---|
68 | ; build the base triangulation with the diamond cut in two triangles |
---|
69 | ; by the vertical diagonal |
---|
70 | ; |
---|
71 | ; first line |
---|
72 | index = lindgen(nx-1) |
---|
73 | trinumber = index |
---|
74 | triangles[0, trinumber] = index |
---|
75 | triangles[1, trinumber] = index+1 |
---|
76 | triangles[2, trinumber] = index+(nx+1-shifted) |
---|
77 | ; last line |
---|
78 | index = (ny-1)*nx+lindgen(nx-1) |
---|
79 | trinumber = numtri(index, nx, ny) |
---|
80 | triangles[0, trinumber] = index |
---|
81 | triangles[1, trinumber] = index+(-nx+((index/nx+1-shifted) MOD 2)) |
---|
82 | triangles[2, trinumber] = index+1 |
---|
83 | ; other lines |
---|
84 | if ny GT 2 then begin |
---|
85 | index = lindgen(nx, ny) |
---|
86 | index = index[0:nx-2, 1:ny-2] |
---|
87 | index = index[*] |
---|
88 | oddeven = (index/nx+1-shifted) MOD 2 |
---|
89 | trinumber = numtri(index, nx, ny) |
---|
90 | triangles[0, trinumber] = index |
---|
91 | triangles[1, trinumber] = index-nx+oddeven |
---|
92 | triangles[2, trinumber] = index+nx+oddeven |
---|
93 | triangles[0, trinumber+1] = index+nx+oddeven |
---|
94 | triangles[1, trinumber+1] = index-nx+oddeven |
---|
95 | triangles[2, trinumber+1] = index+1 |
---|
96 | endif |
---|
97 | ; |
---|
98 | ; cut the diamond specified by singular in two triangles |
---|
99 | ; by the horizontal diagonal |
---|
100 | ; |
---|
101 | IF keyword_set(singular) then BEGIN |
---|
102 | yindex = singular/nx |
---|
103 | otherline = where(yindex NE 0 AND yindex NE (ny-1)) |
---|
104 | if otherline[0] NE -1 then begin |
---|
105 | index = singular[otherline] |
---|
106 | oddeven = (index/nx+1-shifted) MOD 2 |
---|
107 | trinumber = numtri(index, nx, ny) |
---|
108 | triangles[0, trinumber] = index |
---|
109 | triangles[1, trinumber] = index-nx+oddeven |
---|
110 | triangles[2, trinumber] = index+1 |
---|
111 | triangles[0, trinumber+1] = index |
---|
112 | triangles[1, trinumber+1] = index+1 |
---|
113 | triangles[2, trinumber+1] = index+nx+oddeven |
---|
114 | endif |
---|
115 | |
---|
116 | endif |
---|
117 | return, triangles |
---|
118 | end |
---|
119 | |
---|