It's not strange, it's intended behaviour of the playground. See the "about" page of the playground: "[...] In the playground the time begins at 2009-11-10 23:00:00 UTC (determining the significance of this date is an exercise for the reader). This makes it easier to cache programs by giving them deterministic output. [...]"
On Mon, May 08, 2017 at 10:22:14AM -0400, Decker, Ryan C. wrote: > See here: [1]https://play.golang.org/p/EjdQRUnwQF > The weird thing is that time.Now().UnixNano() doesn't appear to ever > change in the playground... > On Mon, May 8, 2017 at 10:21 AM, Decker, Ryan C. <[2]rdec...@siena.edu> > wrote: > > I usually follow the example and go with time.Now().UnixNano() which you > can see here: > On Mon, May 8, 2017 at 10:07 AM, messju mohr > <[3]mes...@lammfellpuschen.de> wrote: > > Hi, > > in xrand() you are initialising r with the same constant seed for > every call, so you always get the same pseudo random number. > > See: <[4]https://play.golang.org/p/XwNmYv5nzJ> > > cheers > messju > > On Mon, May 08, 2017 at 03:26:08AM -0700, > [5]sivarajshabin...@gmail.com wrote: > > Hi All, > > > > Firstly, sorry for the title that sounds like a click bait. I > am not > > understanding what exactly is wrong with this program > > [1][6]https://play.golang.org/p/Tl0wpaCqK7 > > > > package main > > > > import ( > > "fmt" > > "math/rand" > > "runtime" > > ) > > > > func xrand() int { > > r := rand.New(rand.NewSource(99)) > > return r.Int() > > } > > > > func main() { > > fmt.Printf("Version %s\n", runtime.Version()) > > fmt.Printf("looks buggy \t1: %d, 2: %d, 3: %d\n", > xrand(), xrand(), > > xrand()) > > > > r1 := rand.New(rand.NewSource(99)) > > fmt.Printf("Looks fine \t1: %d, 2: %d, 3: %d\n", > r1.Int(), > > r1.Int(), r1.Int()) > > } > > Output>>>> > > > > Version go1.8 > > looks buggy 1: 1108929909, 2: 1108929909, 3: 1108929909 > > Looks find 1: 1108929909, 2: 1298032409, 3: 913431059 > > > > When I generate a random number with "math/rand", like the > example given > > in documentation [2][7]https://play.golang.org/p/O2k_za0AW7 > except that I > > return the randomly generated integer from a function, But the > function > > keeps returning the same value any number of time I call it. On > the > > contrary running the same code from the main generates random > values, > > there isn't a reason to doubt rand package. However in the > second print > > statement where random numbers are properly generated the first > value > > always is the same value returned by xrand(), here there is > something to > > doubt rand package. > > > > What am I missing here? Could it be a bug? > > > > Thanks in advance. > > > > Cheers > > Shabinesh > -- > You received this message because you are subscribed to the Google > Groups "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send > an email to [8]golang-nuts+unsubscr...@googlegroups.com. > For more options, visit [9]https://groups.google.com/d/optout. > > -- > Ryan C. Decker '08 > Sr. Network & Systems Engineer > Siena College ITS > 515 Loudon Road > Loudonville, NY 12211 > [10]rdec...@siena.edu > CONFIDENTIALITY NOTICE: This e-mail, including any attachments, is for > the sole use of the intended recipient(s) and may contain confidential > and privileged information. Any unauthorized review, use, disclosure, or > distribution is prohibited. If you received this e-mail and are not the > intended recipient, please inform the sender by e-mail reply and destroy > all copies of the original message. > > -- > Ryan C. Decker '08 > Sr. Network & Systems Engineer > Siena College ITS > 515 Loudon Road > Loudonville, NY 12211 > [11]rdec...@siena.edu > CONFIDENTIALITY NOTICE: This e-mail, including any attachments, is for the > sole use of the intended recipient(s) and may contain confidential and > privileged information. Any unauthorized review, use, disclosure, or > distribution is prohibited. If you received this e-mail and are not the > intended recipient, please inform the sender by e-mail reply and destroy > all copies of the original message. > > References > > Visible links > 1. https://play.golang.org/p/EjdQRUnwQF > 2. mailto:rdec...@siena.edu > 3. mailto:mes...@lammfellpuschen.de > 4. https://play.golang.org/p/XwNmYv5nzJ > 5. mailto:sivarajshabin...@gmail.com > 6. https://play.golang.org/p/Tl0wpaCqK7 > 7. https://play.golang.org/p/O2k_za0AW7 > 8. mailto:golang-nuts%2bunsubscr...@googlegroups.com > 9. https://groups.google.com/d/optout > 10. mailto:rdec...@siena.edu > 11. mailto:rdec...@siena.edu -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
