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From: Scott S on 15 Jun 2010 22:09
I need a way to interpolate data that was non uniformly sampled so that I can create a histogram. The data collection has three states. While the device is sleeping, the temperature is sampled every 60 mininutes. When the device is cooling, the temperature is sampled every 10min. When the device is heating, the temperature is sampled every 30min. When the device changes state, another temperature sample is taken. Here's some sample data:

time temp

12:07 34F
13:07 34F
14:07 34F
15:07 33F
15:49 33F
15:59 33F
16:09 32F
16:19 31F
16:29 31F
16:31 31F
17:31 31F
18:31 31F
18:23 32F
18:53 33F
19:23 34F

I would like to create a histogram of the temperatures, but I can't use the data directly. The following would be wrong:
31 5
32 2
33 4
34 4

Becuase the 32F at 16:09 is for 10min, but the 32F at 18:23 is for 30min

Please help...
From: Lothar Schmidt on 16 Jun 2010 00:21
Am 16.06.2010 04:09, schrieb Scott S:
> I need a way to interpolate data that was non uniformly sampled so that
> I can create a histogram. The data collection has three states. While
> the device is sleeping, the temperature is sampled every 60 mininutes.
> When the device is cooling, the temperature is sampled every 10min. When
> the device is heating, the temperature is sampled every 30min. When the
> device changes state, another temperature sample is taken. Here's some
> sample data:
>
> time temp
>
> 12:07 34F
> 13:07 34F
> 14:07 34F
> 15:07 33F
> 15:49 33F
> 15:59 33F
> 16:09 32F
> 16:19 31F
> 16:29 31F
> 16:31 31F
> 17:31 31F
> 18:31 31F
> 18:23 32F
> 18:53 33F
> 19:23 34F
>
> I would like to create a histogram of the temperatures, but I can't use
> the data directly. The following would be wrong:
> 31 5
> 32 2
> 33 4
> 34 4
>
> Becuase the 32F at 16:09 is for 10min, but the 32F at 18:23 is for 30min
>
> Please help...

multiply the histogramm data with the mean length of time intervalls for
each temperature... or summ the length time intervalls for any
temperatur and plot versus the temperature

12:07 34F
13:07 34F 1h
14:07 34F 1h
15:07 33F 1h
15:49 33F 42m
15:59 33F 10m
16:09 32F 10m
16:19 31F 10m
16:29 31F 10m
16:31 31F 2m
17:31 31F 1h
18:31 31F 1h
18:23 32F -8m (!)
18:53 33F 30m
19:23 34F 30m

leads to means:
31F 142m
32F 2m
33F 144m
34F 150m

I think this is, what you try to do...
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