Print the bounds of the epoch at various resolution and (signed) integer width

getepoch.go

package main

import "fmt"
import "math"
import "time"

func main() {
  tz, err := time.LoadLocation("UTC")
  if err != nil { // Always check errors even if they should not happen.
	panic(err)
  }

  a := [4]int64{1<<23, 1<<31, 1<<52, math.MaxInt64};

  fmt.Println("Type/Resolution, float, int, double, long/x87 long double");
  fmt.Print("Width");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(math.Log2((float64)(a[x])));
  }
  fmt.Print("\n");
  fmt.Print("1 ns");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.Unix(0, a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("-1 ns");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.Unix(0, -a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("10 ns");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMicro(a[x]/100).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("-10 ns");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMicro(-(a[x]/100)).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("1 us");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMicro(a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("-1 us");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMicro(-a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("1 ms");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMilli(a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("-1 ms");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.UnixMilli(-a[x]).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("1 s");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.Unix(a[x], 0).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
  fmt.Print("-1 s");
  for x := 0; x < len(a); x++ {
  	fmt.Print(", ");
  	fmt.Print(time.Unix(-a[x], 0).In(tz).Format("2006-01-02T15:04"));
  }
  fmt.Print("\n");
 }