Data from Internet Sources
Download daily mean temperatures for the past year for the Great Lakes.
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rawdata =
Import["http://coastwatch.glerl.noaa.gov/ftp/glsea/avgtemps/glsea-\
temps_1024.dat", "Data"];
The observations begin from row 11.
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rawdata[[;; 11]]
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In[3]:=

obs = rawdata[[11 ;;]];
The number of observations.
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Length[obs]
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Define the list of lakes.
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lakes = {"Superior", "Michigan", "Huron", "Erie", "Ontario",
"St. Clair"};
show complete Wolfram Language input
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Create dates to serve as time stamps in the TimeSeries.
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dates = Table[
DatePlus[{obs[[k, 1]], 1, 1}, Quantity[obs[[k, 2]], "Days"]], {k,
1, Length[obs]}];
Use QuantityArray to store the temperatures and the unit.
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values = QuantityArray[obs[[All, 3 ;;]], "DegreesCelsius"]
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Store the list of the lakes as MetaInformation that can be retrieved later, for example, to create plot legends.
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ts = TimeSeries[values, {dates},
MetaInformation -> {"Lakes" -> lakes}]
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In[10]:=

DateListPlot[ts, PlotLegends -> ts["Lakes"], PlotTheme -> "Detailed",
FrameLabel -> Automatic]
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Study descriptive statistics for each lake.
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stats = {Min, Max, Mean, Median, StandardDeviation};
summary[lake_] := Map[#[lake] &, stats]
In[12]:=

TableForm[
Table[summary[ts["PathComponent", k]], {k, 1, Length[lakes]}],
TableHeadings -> {lakes, stats}]
Out[12]//TableForm=
