+
+ my $avhdg = r2d(atan2($sindir, $cosdir));
+ $avhdg += 360 if $avhdg < 0;
+ return {w => nearest(0.1,$wind / $count), d => nearest(0.1,$avhdg)};
+}
+
+# radians to degrees
+sub r2d
+{
+ my $n = shift;
+ return ($n / pi) * 180;
+}
+
+# degrees to radians
+sub d2r
+{
+ my $n = shift;
+ return ($n / 180) * pi;
+}
+
+sub calc_rain
+{
+ my $rain = shift;
+
+ $ld->{rain24} ||= [];
+
+ my $Rain_1h = nearest(0.1, $rain >= $ld->{last_rain_hour} ? $rain - $ld->{last_rain_hour} : $rain); # this is the rate for this hour, so far
+ my $rm = nearest(0.1, $rain >= $ld->{last_rain_min} ? $rain - $ld->{last_rain_min} : $rain);
+ my $Rain_1m = nearest(0.1, $rm);
+ push @{$ld->{rain24}}, $Rain_1m;
+ $ld->{rain_24} += $rm;
+ while (@{$ld->{rain24}} > 24*60) {
+ $ld->{rain_24} -= shift @{$ld->{rain24}};