Re: [sensors] Sensors for continuously changing real valued properties

So I'm not sure I understand this properly. Let me got through your 
comment line by line:

> Sensors may measure continuously changing real valued properties 
where the sensor readings represent piece-wise approximations to the 
value being measured.

So data is either discreet or continuous. If it's discreet, the API 
consumer wants to listen to `onchange` events, if it's continuous, to 
`ondata` events (maybe those should be called `onpolled`). This 
distinction isn't properly made in the spec at the moment and this is 
definitely something I need to work on. From the perspective of the 
API consumer, a remote sensor that would do some transformations to 
turn continuous data into discreet data would appear as the latter.

> The data points could involve time domain or frequency domain 
approximations where each data point conveys several parameters.

I'm not sure about what the first part of this means. Are you 
suggesting a sensor reading could combine multiple readings of the 
same sensor? So that's also one of the areas that need more work, as 
there are clearly requirements for this.

Else are you suggesting that a single reading could include data point
 from multiple sensors? That's sort of the case, for example a 
barometer reading could include the output of the temperature sensor 
it most certainly contains as well as the derived pressure.

> The data points could be at a fixed interval, or at irregular 
intervals where each data point is associated with a timestamp.

So that seems taken care of already.

> Piece-wise approximations enable a reduction in the number of data 
points required to adequately represent the measured property.

Yes, but that is not really something the API consumers need to worry 
about, is it?

> The generic sensor API spec should identify this design pattern and 
provide guidance.

So I'm not sure what you mean by this other than the points I've noted
 above (clear way to specify multiple readings in one event, 
distinction between pushed and polled data, and ability to have 
complex sensors with multiple properties).

-- 
GitHub Notif of comment by tobie
See https://github.com/w3c/sensors/issues/68#issuecomment-156062204

Received on Thursday, 12 November 2015 10:26:37 UTC