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How to determine the date of the first channel entry point
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turgo

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January 16, 2018 - 2:55 pm
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I'm trying to determine the date of the first channel entry point.  This would seem a simple exercise, but there are problems.  For example, downloading the channel yield a 500 mb file which is impossible to open.  Using thingspeak read with a broad range of dates yields only the ending points.  If the dates are both prior to the channel start, an error is generated.  What do I do?

 

It would be really helpful for thingspeak read to have the ability to return points by index value.

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Vinod

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January 16, 2018 - 5:52 pm
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If have the file on a Linux computer, you can use the head command. If you are on Windows, you will need to open up a powershell and execute

get-content c:\path_to_file\your_file_name -totalcount 10

to get the first 10 lines.

Out of curiosity, of this 500MB of data how much of it is critical to you and how do you use it?

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turgo

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January 16, 2018 - 7:02 pm
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I use the data in realtime as a gage.  Rapid update is important.  However, I don't need this kind of resolution in the historical data, hence my other threads about consolidating my data.  Is there a unix shell command that will work on the mac OS?

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Vinod

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January 16, 2018 - 7:30 pm
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The head command should work on the Mac. Try

head -n 10 filename.csv

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turgo

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January 20, 2018 - 1:29 am
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I found another way.  First, start downloading the entire channel; then cancel the download; finally open the small file containing the first points.

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