Time confusion?

[John W. Eaton]

On 10-Mar-2004, Vic Norton <address@hidden> wrote:

After seeing Paul's reply, I decided to take another look at this.
I'll reorder your post a bit so the output directly follows the input:

| date0 = '23-Feb-04'
| date0 = 23-Feb-04
| tm_struct1 = strptime(date0, "%e-%b-%y")
| tm_struct1 =
| {
|    hour = 0
|    isdst = 0
|    mday = 23
|    min = 0
|    mon = 1
|    sec = 0
|    usec = 0
|    wday = 0
|    yday = 0
|    year = 104
|    zone =
| }

Here is what I see (using 2.1.53 on a Debian testing system):

  octave:1> date0 = '23-Feb-04'
  date0 = 23-Feb-04
  octave:2> tm_struct1 = strptime(date0, "%e-%b-%y")
  tm_struct1 =
  {
    hour = 0
    isdst = 0
    mday = 23
    min = 0
    mon = 1
    sec = 0
    usec = 0
    wday = 1
    yday = 53
    year = 104
    zone =
  }

Note that my strptime fills in the wday and yday fields and yours did
not.

| date1 = strftime("%a, %e-%b-%y", tm_struct1)
| date1 = Sun, 23-Feb-04

I see

  octave:3> date1 = strftime("%a, %e-%b-%y", tm_struct1)
  date1 = Mon, 23-Feb-04

However, if I modify my time structure to be the same as yours, then I
obtain the same result that you see:

  octave:5> tm_struct1.wday = 0;
  octave:6> tm_struct1.yday = 0;
  octave:7> date1 = strftime("%a, %e-%b-%y", tm_struct1)
  date1 = Sun, 23-Feb-04

The key seems to be the setting of wday:

  octave:9> tm_struct1.wday = 5;
  octave:10> date1 = strftime("%a, %e-%b-%y", tm_struct1)
  date1 = Fri, 23-Feb-04

Odd, but if this is a bug, then it is not really a bug in Octave,
since Octave just relies on the C library functions to do the right
thing.

So, why does the strptime function on your system not return wday == 1
for 23 Feb 2004?

jwe



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