diff options
author | Mattias Andrée <maandree@kth.se> | 2019-10-06 09:36:23 +0200 |
---|---|---|
committer | Mattias Andrée <maandree@kth.se> | 2019-10-06 09:36:23 +0200 |
commit | 1be48c64b4e5df9e9b1ad69b3bb30b867b0abf9e (patch) | |
tree | 697f6c2fb5f3f91ab64e6ed32c45e483bf31e442 /man/libred_solar_elevation.3 | |
parent | Add golden hour and blue hour (diff) | |
download | libred-1be48c64b4e5df9e9b1ad69b3bb30b867b0abf9e.tar.gz libred-1be48c64b4e5df9e9b1ad69b3bb30b867b0abf9e.tar.bz2 libred-1be48c64b4e5df9e9b1ad69b3bb30b867b0abf9e.tar.xz |
Clean up
Signed-off-by: Mattias Andrée <maandree@kth.se>
Diffstat (limited to 'man/libred_solar_elevation.3')
-rw-r--r-- | man/libred_solar_elevation.3 | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/man/libred_solar_elevation.3 b/man/libred_solar_elevation.3 new file mode 100644 index 0000000..7fd499f --- /dev/null +++ b/man/libred_solar_elevation.3 @@ -0,0 +1,48 @@ +.TH LIBRED_SOLAR_ELEVATION 3 LIBRED +.SH NAME +libred_solar_elevation \- Calculate the Sun's apparent elevation +.SH SYNOPSIS +.nf +#include <libred.h> + +double \fBlibred_solar_elevation\fP(double \fIlatitude\fP, double \fIlongitude\fP); +.fi +.PP +Link with +.IR -lred . +.SH DESCRIPTION +.B libred_solar_elevation +calculates the Sun's elevation as apparent from a select geographical position. +Namely from +.I latitude +degrees north of GPS's equator and +.I longitude +degrees east of GPS's prime meridian. The function is only explicitly defined for +values between -90 and +90 for +.I latitude +and values between -180 and +180 for and +.IR longitude . +Other values may or may not work, no error is thrown if used. +.SH "RETURN VALUE" +Upon successful completion, the function sets +.B errno +to 0 and returns the Sun's current apparent elevation, measured in +degrees above the horizon. On failure, the function returns an +arbitrary value (happens to always be 0.0) and sets +.B errno +an a non-zero value. +.SH ERRORS +The function may fail for any reason specified for +.BR clock_gettime (3), +and set the value of +.B errno +to the same values. +.B errno +is always set to 0 on success. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.BR libred.h (0), +.BR libred (7), +.BR libred_check_timetravel (3), +.BR libred_init_colour (3) |