ThingSpeak

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I've got below timetable with daily measurements from my gas meter at home: Timestamps GasM3 ____________________ _____________ 14-Aug-2019 00:00:00 331.15 25-Aug-2019 00:00:00 332.37 26-Aug-2019 00:00:00 332.74 27-Aug-2019 00:00:00 333.97 I would like to know the daily consumption, so I tried playing with "differentiate" & "diff" to get these values in a new table. I've tried Test1 = differentiate(DailyGasDataTimeTable) which gave the following error: Error using Visualization: Differential test</a> (line 17</a>) 'differentiate' requires Curve Fitting Toolbox and Test2 = diff(DailyGasDataTimeTable) which gave the following error: Undefined function 'diff' for input arguments of type 'table'. Error in Visualization: Differential test (line 17) Unfortunately I'm stuck, please advise. Kind regards, Daniel

The sample timetable below needs to be aggregated hourly with the retime function. The text numbers which sometimes appear in my data feed cause an error at the retime function. How do I convert the timetable to all numeric data? The source is a ThingSpeak channel. There is 5 gigabytes of this data to process. Mathworks has no facility to fix or change data already recorded within the feed. The timetable is created with the Mathworks command thingspeakread, so I don't have table input options. I'm hoping that there is some command that applies to the whole time table, preserves the numeric data, and converts the text numbers to numeric data. 10×7 timetable Timestamps x1stFloor x2ndFloor x3rdFloor Slab EarthTube SlabCoolingIn SlabCoolingOut ____________________ _________ _________ _________ ____ _________ _____________ ______________ 06-Apr-2013 08:20:55 '103.72' 100 NaN NaN NaN NaN NaN 06-Apr-2013 08:21:10 '103.72' 101 NaN NaN NaN NaN NaN 06-Apr-2013 08:21:26 '102.84' 102 NaN NaN NaN NaN NaN 06-Apr-2013 08:21:41 '102.84' 103 NaN NaN NaN NaN NaN