nathan-osman / go-sunrise

Go package for calculating the sunrise and sunset times for a given location

go-sunrise

Go package for calculating the sunrise and sunset times for a given location based on this method.

Usage

To calculate sunrise and sunset times, you will need the following information:

• the date for which you wish to calculate the times
• the latitude and longitudinal coordinates of the location

Begin by importing the package:

import "github.com/nathan-osman/go-sunrise"

Next, feed the information into the SunriseSunset() method:

rise, set := sunrise.SunriseSunset(
    43.65, -79.38,          // Toronto, CA
    2000, time.January, 1,  // 2000-01-01
)

The two return values will be the sunrise and sunset times for the location on the given day as time.Time values. If sun does not rise or set, both return values will be time.Time{}.

go-sunrise's Issues

Sometimes the sun never sets

Hey, thanks for this library. Been using it to automatically dim a LED display overnight.

Wanted to mention that stuff breaks a bit for locations and times when/where the sun never sets. E.g.:

a, b := sunrise.SunriseSunset(69.3321443, -81.6781126, 2020, 6, 15)
fmt.Println("Igloolik, Canada:", a, b)

Produces Igloolik, Canada: 292277026596-12-04 15:30:08 +0000 UTC 292277026596-12-04 15:30:08 +0000 UTC. That looks a bit like time.Unix(1<<63-1, 0). Guessing this isn't intentional?