Calculate number of days between two dates? - time

Question

How can I calculate the number of days between two dates? In the code below I should get the number of hours, which means that I should only need to divide by 24. However, the result I get is something like -44929.000000. I'm only looking a day or two back so I would expect 24 or 48 hours.
package main
import (
"fmt"
"time"
)
func main() {
timeFormat := "2006-01-02"
t, _ := time.Parse(timeFormat, "2014-12-28")
fmt.Println(t)
// duration := time.Since(t)
duration := time.Now().Sub(t)
fmt.Printf("%f", duration.Hours())
}
Here's the executable Go code: http://play.golang.org/p/1MV6wnLVKh

Answer 1

Your program seems to work as intended. I'm getting 45.55 hours. Have you tried to run it locally?
Playground time is fixed, time.Now() will give you 2009-11-10 23:00:00 +0000 UTC always.

Answer 2

package main
import (
"fmt"
"time"
)
func main() {
date := time.Now()
fmt.Println(date)
format := "2006-01-02 15:04:05"
then,_ := time.Parse(format, "2007-09-18 11:58:06")
fmt.Println(then)
diff := date.Sub(then)
//func Since(t Time) Duration
//Since returns the time elapsed since t.
//It is shorthand for time.Now().Sub(t).
fmt.Println(diff.Hours())// number of Hours
fmt.Println(diff.Nanoseconds())// number of Nanoseconds
fmt.Println(diff.Minutes())// number of Minutes
fmt.Println(diff.Seconds())// number of Seconds
fmt.Println(int(diff.Hours()/24))// number of days
}
Here is the running code https://play.golang.org/p/Vbhh1cBKnh

Answer 3

the below code gives the list of all the days along with the number of days between the from date and to date:
you can click on the link for the code in
Go PlayGround:https://play.golang.org/p/MBThBpTqjdz
to := time.Now()
from := to.AddDate(0, -1, 0)
fmt.Println("toDate", to)
fmt.Println("fromDate", from)
days := to.Sub(from) / (24 * time.Hour)
fmt.Println("days", int(days))
noofdays := int(days)
for i := 0; i <= noofdays; i++ {
fmt.Println(from.AddDate(0, 0, i))
}

Answer 4

One caveat to be mindful of when using this technique of timeOne.Sub(timeTwo).Hours() / 24 is that daylights savings can cause a day to contain only 23 hours, throwing this calculation off slightly.

Answer 5

Happy programmer's day
package main
import (
"fmt"
"time"
)
func main() {
loc, _ := time.LoadLocation("UTC")
now := time.Now().In(loc)
firstDate := time.Date(now.Year(), 1, 1, 0, 0, 0, 0, loc)
diff := now.Sub(firstDate)
fmt.Printf("The difference between %s and today %s es %d days\n", now.String(), firstDate.String(), int(diff.Hours()/24)+1)
// Just a joke
if ( int(diff.Hours()/24)+1 == 256 ) {
fmt.Printf("¡Happy programmer's day!")
} else {
fmt.Printf("On my computer it works...!?")
}
}