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This may be a bit of an odd one but hopefully shouldn't be too hard for somebody with a little more knowledge than me. I'm currently using a tool called Joulemeter on my laptop. This program measures the power usage of my machine and saves the data as a CSV text file.

Here's an example of the outputted readings:

TimeStamp (ms), Total Power (W), CPU (W), Monitor (W), Disk (W), Base (W), Application (W)
63465092415703,16.1,0.1,7.3,0.0,8.7,--
63465092416716,16.2,0.3,7.3,0.0,8.7,--
63465092417730,17.2,1.3,7.3,0.0,8.7,--
63465092418744,16.2,0.3,7.3,0.0,8.7,--
63465092419774,16.1,0.1,7.3,0.0,8.7,--
63465092420786,17.1,1.1,7.3,0.0,8.7,--

So I'm mainly interested in the total power usage over a certain time, for example taking a reading over 8 hours and calculating the total power usage. If anyone can point me in the right direction with they I'd be very grateful. I was hoping to use Excel to display this information and finding a equation to display the timestamp is a formatted time and date is causing me particular trouble.

Thanks for readin ^_^

JonnyIrving
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1 Answers1

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In order to display the TimeStamp as a date/time in Excel, you need to scale it into a TimerSerial number and then format it to display what you want.

To scale it you need to know what the base of your TimeStamp is (ie what date is a TimeStamp of 0) and calculate the offset to Excel time.

Excel time can use either 1900 or 1904 as the base date. See this MS article.

To convert your TimeStamps, use the formula

=(+A1-Offset)/86400000

where Offset is a calculated value to align the two systems. Eg if the TimeStamp's in your example data occured on 31 Jan 2012, Offset = 59,927,882,400,000.

To display the result as a date/time, format it to the precission you require,
eg yyyy/mm/dd hh:mm:ss.000 will display date and time to the ms.

This would make the first line in your sample 2012/01/31 22:20:15.703

chris neilsen
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