I've been examining the GPS recordings of walks made on my iPhone. The
GPX files should of course contain one text line for each position
recorded, containing position, altitude and a timestamp. But
occasionally (less than 1%) the timestamp is obviously missing. The
4th line of this small extract shows an example:
<trkpt lat="50.5573525932" lon="-4.9283242878"><ele>22</ele><time>2016-08-03T09:58:07Z</time></trkpt>
<trkpt lat="50.5573393079" lon="-4.9283319153"><ele>22</ele></trkpt>
<trkpt lat="50.5573267350" lon="-4.9283414707"><ele>22</ele><time>2016-08-03T09:58:08Z</time></trkpt>
How does that flaw arise please? I can understand that for various
reasons, recorded trackpoints may be missing completely, or wildly inaccurate. But how can some be without a timestamp?
Terry Pinnell wrote:
I've been examining the GPS recordings of walks made on my iPhone. The
GPX files should of course contain one text line for each position
recorded, containing position, altitude and a timestamp. But
occasionally (less than 1%) the timestamp is obviously missing. The
4th line of this small extract shows an example:
<trkpt lat="50.5573525932"
lon="-4.9283242878"><ele>22</ele><time>2016-08-03T09:58:07Z</time></trkpt> >>
<trkpt lat="50.5573393079" lon="-4.9283319153"><ele>22</ele></trkpt>
<trkpt lat="50.5573267350"
lon="-4.9283414707"><ele>22</ele><time>2016-08-03T09:58:08Z</time></trkpt> >>
How does that flaw arise please? I can understand that for various
reasons, recorded trackpoints may be missing completely, or wildly
inaccurate. But how can some be without a timestamp?
Note that the two surrounding track points have just one second between
them: I'm guessing your logging app skips the timestamp when it is
identical to the previous one.
A very simple parser that ust picks up fields as it finds them will
remember the previosu timestamp and repeat it.
Terje
I've been examining the GPS recordings of walks made on my iPhone. The
GPX files should of course contain one text line for each position
recorded, containing position, altitude and a timestamp. But
occasionally (less than 1%) the timestamp is obviously missing. The
4th line of this small extract shows an example:
<trkpt lat="50.5573593826" lon="-4.9283146486"><ele>22</ele><time>2016-08-03T09:57:59Z</time></trkpt>
<trkpt lat="50.5573615199" lon="-4.9283183366"><ele>22</ele><time>2016-08-03T09:58:06Z</time></trkpt>
<trkpt lat="50.5573525932" lon="-4.9283242878"><ele>22</ele><time>2016-08-03T09:58:07Z</time></trkpt>
<trkpt lat="50.5573393079" lon="-4.9283319153"><ele>22</ele></trkpt>
<trkpt lat="50.5573267350" lon="-4.9283414707"><ele>22</ele><time>2016-08-03T09:58:08Z</time></trkpt>
<trkpt lat="50.5573160900" lon="-4.9283459131"><ele>21</ele><time>2016-08-03T09:58:10Z</time></trkpt>
<trkpt lat="50.5573066185" lon="-4.9283490144"><ele>22</ele><time>2016-08-03T09:58:11Z</time></trkpt>
<trkpt lat="50.5573010445" lon="-4.9283564743"><ele>22</ele><time>2016-08-03T09:58:12Z</time></trkpt>
<trkpt lat="50.5572247692" lon="-4.9284306541"><ele>21</ele><time>2016-08-03T09:58:20Z</time></trkpt>
How does that flaw arise please? I can understand that for various
reasons, recorded trackpoints may be missing completely, or wildly inaccurate. But how can some be without a timestamp?
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