CMLogItem timestamp: Why so complicated?
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1
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I receive a CMLogItem from a CoreMotion query in swift (could be accelerometer, gyroscope). Now, I want to get the timestamp of that sample, preferably as a Date() object. CMLogItems have a property .timestamp of type TimeInterval.
The documentation tells me the following:
The CMLogItem class defines a read-only timestamp property that
records the time a motion-event measurement was taken.
However, I am not sure how to convert this timestamp to a Date() object because I dont know what the timestamp is referring to.
Another documentation says:
The timestamp is the amount of time in seconds since the device
booted.
But this seems really weird and I dont understand why apple would create such an inconsistent and complicated API.
swift core-motion
asked Nov 11 at 16:10
DeveloBär
467517
add a comment |
up vote
1
down vote
favorite
I receive a CMLogItem from a CoreMotion query in swift (could be accelerometer, gyroscope). Now, I want to get the timestamp of that sample, preferably as a Date() object. CMLogItems have a property .timestamp of type TimeInterval.
The documentation tells me the following:
The CMLogItem class defines a read-only timestamp property that
records the time a motion-event measurement was taken.
However, I am not sure how to convert this timestamp to a Date() object because I dont know what the timestamp is referring to.
Another documentation says:
The timestamp is the amount of time in seconds since the device
booted.
But this seems really weird and I dont understand why apple would create such an inconsistent and complicated API.
swift core-motion
asked Nov 11 at 16:10
DeveloBär
467517
add a comment |
up vote
1
down vote
favorite
up vote
1
down vote
favorite
I receive a CMLogItem from a CoreMotion query in swift (could be accelerometer, gyroscope). Now, I want to get the timestamp of that sample, preferably as a Date() object. CMLogItems have a property .timestamp of type TimeInterval.
The documentation tells me the following:
The CMLogItem class defines a read-only timestamp property that
records the time a motion-event measurement was taken.
However, I am not sure how to convert this timestamp to a Date() object because I dont know what the timestamp is referring to.
Another documentation says:
The timestamp is the amount of time in seconds since the device
booted.
But this seems really weird and I dont understand why apple would create such an inconsistent and complicated API.
swift core-motion
asked Nov 11 at 16:10
DeveloBär
467517
I receive a CMLogItem from a CoreMotion query in swift (could be accelerometer, gyroscope). Now, I want to get the timestamp of that sample, preferably as a Date() object. CMLogItems have a property .timestamp of type TimeInterval.
The documentation tells me the following:
The CMLogItem class defines a read-only timestamp property that
records the time a motion-event measurement was taken.
However, I am not sure how to convert this timestamp to a Date() object because I dont know what the timestamp is referring to.
Another documentation says:
The timestamp is the amount of time in seconds since the device
booted.
But this seems really weird and I dont understand why apple would create such an inconsistent and complicated API.
swift core-motion
swift core-motion
asked Nov 11 at 16:10
DeveloBär
467517
asked Nov 11 at 16:10
DeveloBär
467517
asked Nov 11 at 16:10
DeveloBär
467517
asked Nov 11 at 16:10
DeveloBär
467517
asked Nov 11 at 16:10
DeveloBär
467517
467517
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
up vote
0
down vote
accepted
I think I figured it out.
The documentation is just wrong here.
It is not the "time in seconds since the device booted" — it is indeed the time since their reference date.
Fix:
extension CMLogItem
func startTime() -> Date
return Date(timeIntervalSinceReferenceDate: self.timestamp)
answered Nov 11 at 16:31
DeveloBär
467517
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
accepted
I think I figured it out.
The documentation is just wrong here.
It is not the "time in seconds since the device booted" — it is indeed the time since their reference date.
Fix:
extension CMLogItem
func startTime() -> Date
return Date(timeIntervalSinceReferenceDate: self.timestamp)
answered Nov 11 at 16:31
DeveloBär
467517
add a comment |
up vote
0
down vote
accepted
I think I figured it out.
The documentation is just wrong here.
It is not the "time in seconds since the device booted" — it is indeed the time since their reference date.
Fix:
extension CMLogItem
func startTime() -> Date
return Date(timeIntervalSinceReferenceDate: self.timestamp)
answered Nov 11 at 16:31
DeveloBär
467517
add a comment |
up vote
0
down vote
accepted
up vote
0
down vote
accepted
I think I figured it out.
The documentation is just wrong here.
It is not the "time in seconds since the device booted" — it is indeed the time since their reference date.
Fix:
extension CMLogItem
func startTime() -> Date
return Date(timeIntervalSinceReferenceDate: self.timestamp)
answered Nov 11 at 16:31
DeveloBär
467517
I think I figured it out.
The documentation is just wrong here.
It is not the "time in seconds since the device booted" — it is indeed the time since their reference date.
Fix:
extension CMLogItem
func startTime() -> Date
return Date(timeIntervalSinceReferenceDate: self.timestamp)
answered Nov 11 at 16:31
DeveloBär
467517
answered Nov 11 at 16:31
DeveloBär
467517
answered Nov 11 at 16:31
DeveloBär
467517
answered Nov 11 at 16:31
DeveloBär
467517
467517
add a comment |
add a comment |
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