# Need Query form to extract Min and Max DateList values for PlotRange from a Dataset

(* SUMMARY - In a Dataset holding DateList entries, how do I extract a minimum and maximum DateList value to pass into DateListPlot's PlotRange specification? See QUESTION further below *)

(* Sample dataset. Actual dataset is much larger. My goal is to create a time series animation where the PlotRange has fixed dimensions for the X/Y axis *)

aDataSet =Dataset[{
}];


dateRange=Sort[aDataSet[[All,"aDate"]]]/@ {First,Last};


(* PlotRange for duration *)

durationRange = Sort[aDataSet[[All,"aDuration"]]]/@ {First,Last};


(* QUESTION - how should I compute dateRange such that it is a form that can be used in PlotRange for DateListPlot? Otherwise, the following will fail because the computed form of dateRange is a Dataset. DateListPlot is expecting a List whose values are the min and maximum dates for the x-axis *)

DateListPlot[aDataSet[[All,{"aDate", "aDuration"}]],Joined->False,
PlotRange->{dateRange,durationRange}]

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• Thank you for taking a moment to re-formatting my inquiry to improve its readability! – A Chase Turner Apr 6 '15 at 11:39

I think your running into trouble with those "24." as the last entry in your date list. That should be a number instead of a string.

aDataSet =Dataset[{
}];


With it as a number then the following would work.

aDataSet[All, "aDate", DateObject][{Max, Min}] // Normal


It gets All of the "aDate" values and converts them into DateObjects. The gets the Min and Max and takes it out of the dataset and into a regular list.

Hope this helps.

• BINGO -- Thank you for catching the data typo ... but more importantly, your sample code here answered my issue -- thank you! – A Chase Turner Apr 6 '15 at 11:41
• @AChaseTurner you can also use MinMax instead of {Min, Max}, if you have 10.1. – Taliesin Beynon Apr 7 '15 at 21:42
• Thank you -- I am using 10.1 and MinMax works for me! – A Chase Turner Apr 8 '15 at 23:57