1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
! $Id: x03f.f90 11680 2011-03-27 17:57:51Z airwin $
! Generates polar plot with, 1-1 scaling
!
! Copyright (C) 2004 Alan W. Irwin
!
! This file is part of PLplot.
!
! PLplot is free software; you can redistribute it and/or modify
! it under the terms of the GNU Library General Public License as
! published by the Free Software Foundation; either version 2 of the
! License, or (at your option) any later version.
!
! PLplot is distributed in the hope that it will be useful,
! but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
! GNU Library General Public License for more details.
!
! You should have received a copy of the GNU Library General Public
! License along with PLplot; if not, write to the Free Software
! Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
use plplot, PI => PL_PI
implicit none
character*3 text
real(kind=plflt) x0(0:360), y0(0:360)
real(kind=plflt) x(0:360), y(0:360), dtr, theta, dx, dy, r, offset
integer i, j, nsp
! Process command-line arguments
call plparseopts(PL_PARSE_FULL)
! Set orientation to portrait - note not all device drivers
! support this, in particular most interactive drivers do not.
call plsori(1)
dtr = PI/180.0_plflt
do i=0,360
x0(i) = cos(dtr * dble (i))
y0(i) = sin(dtr * dble (i))
enddo
! Initialize PLplot
call plinit()
! Set up viewport and window, but do not draw box
call plenv(-1.3_plflt, 1.3_plflt, -1.3_plflt, 1.3_plflt, 1, -2)
! Draw circles for polar grid
do i = 1,10
call plarc(0.0_plflt, 0.0_plflt, 0.1_plflt*i, 0.1_plflt*i, &
0.0_plflt, 360.0_plflt, 0.0_plflt, 0)
enddo
call plcol0(2)
do i = 0,11
theta = 30.0_plflt*i
dx = cos(dtr*theta)
dy = sin(dtr*theta)
! Draw radial spokes for polar grid
call pljoin(0.0_plflt, 0.0_plflt, dx, dy)
write (text,'(i3)') nint(theta)
! Write labels for angle
text = text(nsp(text):)
if (theta .lt. 9.99) then
offset = 0.45
elseif (theta .lt. 99.9) then
offset = 0.30
else
offset = 0.15
endif
! Slightly off zero to avoid floating point logic flips at
! 90 and 270 deg.
if (dx.ge.-0.00001_plflt) then
call plptex(dx, dy, dx, dy, -offset, text)
else
call plptex(dx, dy, -dx, -dy, 1._plflt+offset, text)
end if
enddo
! Draw the graph
do i=0,360
r = sin(dtr*dble (5*i))
x(i) = x0(i) * r
y(i) = y0(i) * r
enddo
call plcol0(3)
call plline(x,y)
call plcol0(4)
call plmtex('t', 2.0_plflt, 0.5_plflt, 0.5_plflt, &
'#frPLplot Example 3 - r(#gh)=sin 5#gh')
! Close the plot at end
call plend
end
integer function nsp(text)
! ==================
! Find first non-space character
use plplot
implicit none
character*(*) text
integer l, len
l = len(text)
nsp = 1
do while(text(nsp:nsp).eq.' ' .and. nsp.lt.l)
nsp = nsp+1
enddo
end
|
