#
# $Id$
#
+# 2001/09/15 some changes to take care of cases where the object
+# doesn't rise or set on a given day...
package Sun;
my $lon = shift;
my $sun0_moon1=shift; # 0 for sun, 1 for moon, 2 for venus...
+ my $norise = 0;
+ my $noset = 0;
+ my ($risehr,$risemin,$risetime,$sethr,$setmin,$settime);
+
my ($alpha1,$alpha2,$alpha3,$delta1,$delta2,$delta3);
my ($m0,$m1,$m2,$theta,$alpha,$delta,$H,$az,$h,$h0,$aznow,$hnow,$corr);
my ($i,$arg,$argtest,$H0,$alphanow,$deltanow,$distance,$distancenow);
}
$arg = (sindeg($h0)-sindeg($lat)*sindeg($delta2))/(cosdeg($lat)*cosdeg($delta2));
- $argtest = tandeg($lat)*tandeg($delta2);
-
- if ( $argtest < -1. ) {
- return sprintf("Doesn't rise.");
- }
- if ( $argtest > 1. ) {
- return sprintf("Doesn't set.");
- }
+ if ( abs($arg) > 1. ) { # either up all day or down all day
+ $norise = 1; # leave it to the user to examine
+ $noset = 1; # the elevation angle (or look outside!)
+ } # to figure out which.
$H0 = acos($arg)*$r2d;
my $aa=$alpha2-$alpha1;
$m0=$m0-1 if( $m0 > 1 );
}
- $m1 = $m0 - $H0/360.;
- $m1=$m1+1 if( $m1 < 0 );
- $m1=$m1-1 if( $m1 > 1 );
- for ($i=1; $i<=2; $i++) {
- $theta = $theta0+360.985647*$m1;
- $alpha=$alpha2+$m1*($aa+$ba+$m1*$ca)/2;
- $delta=$delta2+$m1*($ad+$bd+$m1*$cd)/2;
- $H=$theta-$lon-$alpha;
- $H=reduce_angle_to_360($H);
- ($az,$h)=get_az_el($H,$delta,$lat);
- $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
- $m1=$m1+$corr;
+
+ if( !$norise ){
+ $m1 = $m0 - $H0/360.;
$m1=$m1+1 if( $m1 < 0 );
$m1=$m1-1 if( $m1 > 1 );
+ for ($i=1; $i<=2; $i++) {
+ $theta = $theta0+360.985647*$m1;
+ $alpha=$alpha2+$m1*($aa+$ba+$m1*$ca)/2;
+ $delta=$delta2+$m1*($ad+$bd+$m1*$cd)/2;
+ $H=$theta-$lon-$alpha;
+ $H=reduce_angle_to_360($H);
+ ($az,$h)=get_az_el($H,$delta,$lat);
+ $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
+ $m1=$m1+$corr;
+ $norise=1 if( $m1 < 0 || $m1 > 1);
+ }
}
- $m2 = $m0 + $H0/360.;
- $m2=$m2+1 if( $m2 < 0 );
- $m2=$m2-1 if( $m2 > 1 );
- for ($i=1; $i<=2; $i++) {
- $theta = $theta0+360.985647*$m2;
- $alpha=$alpha2+$m2*($aa+$ba+$m2*$ca)/2;
- $delta=$delta2+$m2*($ad+$bd+$m2*$cd)/2;
- $H=$theta-$lon-$alpha;
- $H=reduce_angle_to_360($H);
- ($az,$h)=get_az_el($H,$delta,$lat);
- $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
- $m2 = $m2 + $corr;
+ if( !$norise ) {
+ $risehr=int($m1*24);
+ $risemin=($m1*24-int($m1*24))*60+0.5;
+ if ( $risemin >= 60 ) {
+ $risemin=$risemin-60;
+ $risehr=$risehr+1;
+ }
+ $risetime=sprintf("%02d:%02dZ",$risehr,$risemin);
+ } else {
+ $risetime="NoRise";
+ }
+
+ if( !$noset ){
+ $m2 = $m0 + $H0/360.;
$m2=$m2+1 if( $m2 < 0 );
$m2=$m2-1 if( $m2 > 1 );
+ for ($i=1; $i<=2; $i++) {
+ $theta = $theta0+360.985647*$m2;
+ $alpha=$alpha2+$m2*($aa+$ba+$m2*$ca)/2;
+ $delta=$delta2+$m2*($ad+$bd+$m2*$cd)/2;
+ $H=$theta-$lon-$alpha;
+ $H=reduce_angle_to_360($H);
+ ($az,$h)=get_az_el($H,$delta,$lat);
+ $corr=($h-$h0)/(360*(cosdeg($delta)*cosdeg($lat)*sindeg($H)));
+ $m2 = $m2 + $corr;
+ $noset=1 if( $m2 < 0 || $m2 > 1);
+ }
}
- my ($risehr,$risemin,$sethr,$setmin);
- $risehr=int($m1*24);
- $risemin=($m1*24-int($m1*24))*60+0.5;
- if ( $risemin >= 60 ) {
- $risemin=$risemin-60;
- $risehr=$risehr+1;
- }
- $sethr=int($m2*24);
- $setmin=($m2*24-int($m2*24))*60+0.5;
- if ( $setmin >= 60 ) {
- $setmin=$setmin-60;
- $sethr=$sethr+1;
- }
+
+ if( !$noset ) {
+ $sethr=int($m2*24);
+ $setmin=($m2*24-int($m2*24))*60+0.5;
+ if ( $setmin >= 60 ) {
+ $setmin=$setmin-60;
+ $sethr=$sethr+1;
+ }
+ $settime=sprintf("%02d:%02dZ",$sethr,$setmin);
+ } else {
+ $settime="NoSet ";
+ }
+
if ( $sun0_moon1 == 0 ) {
- return (sprintf("%02d:%02dZ", $risehr,$risemin), sprintf("%02d:%02dZ",$sethr,$setmin),$aznow+180,$hnow);
+ return (sprintf("%s", $risetime), sprintf("%s",$settime),$aznow+180,$hnow);
}
if ( $sun0_moon1 == 1 ) {
- return (sprintf("%02d:%02dZ", $risehr,$risemin), sprintf("%02d:%02dZ",$sethr,$setmin),
+ return (sprintf("%s", $risetime), sprintf("%s",$settime),
$aznow+180,$hnow, -40*log10($distance/385000) );
}
}