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DataSets[Quandl]

 Reference
 create a reference to Quandl data

 Calling Sequence Reference(id) DataSets:-Reference("Quandl", id)

Parameters

 id - string; Quandl identifier for the data set

Description

 • The Reference command creates a reference to a Quandl data set, and retrieves some metadata about the data available for this data set.
 • The two calling sequences are exactly equivalent: a call to Reference in the DataSets package interprets its first argument as the name of a data source, and if it is "Quandl", it calls DataSets[Quandl][Reference].
 • The reference object retrieves the data only when necessary, which is when it is implicitly or explicitly converted to another type.
 • Retrieved data is cached so that subsequent conversions will be faster.
 • Reference objects can be created without specifying the Quandl identifier with DataSets[Search] or DataSets[InsertSearchBox].
 • Quandl reference objects are compatible with any command in the TimeSeriesAnalysis package that makes use of TimeSeries objects.

Examples

 > $\mathrm{with}\left(\mathrm{DataSets}\right):$

We create a reference by identifier.

 > $\mathrm{ref}≔\mathrm{Reference}\left("Quandl","FRED/CANPOPL"\right)$
 ${\mathrm{ref}}{≔}\left[\begin{array}{c}{\mathrm{Data set}}\\ {\mathrm{Population in Canada \left(DISCONTINUED\right)}}\\ {\mathrm{Quandl FRED/CANPOPL}}\\ {\mathrm{up to 52 rows \left(annual\right), 1 column}}\\ {\mathrm{1960-01-01 - 2011-01-01}}\end{array}\right]$ (1)

This is equivalent to

 > $\mathrm{Quandl}:-\mathrm{Reference}\left("FRED/CANPOPL"\right)$
 $\left[\begin{array}{c}{\mathrm{Data set}}\\ {\mathrm{Population in Canada \left(DISCONTINUED\right)}}\\ {\mathrm{Quandl FRED/CANPOPL}}\\ {\mathrm{up to 52 rows \left(annual\right), 1 column}}\\ {\mathrm{1960-01-01 - 2011-01-01}}\end{array}\right]$ (2)
 > $\mathrm{GetIdentifier}\left(\mathrm{ref}\right)$
 ${"FRED/CANPOPL"}$ (3)
 > $\mathrm{convert}\left(\mathrm{ref},'\mathrm{Matrix}'\right)$
 ${{\mathrm{_rtable}}}_{{36893628615597383300}}$ (4)
 > $\mathrm{with}\left(\mathrm{TimeSeriesAnalysis}\right):$
 > $\mathrm{TimeSeriesPlot}\left(\mathrm{ref}\right)$

 > $\mathrm{esm}≔\mathrm{ExponentialSmoothingModel}\left(\mathrm{ref}\right)$
 ${\mathrm{TimeSeriesAnalysis}}{:-}{\mathrm{ExponentialSmoothingModel}}{}\left({\mathrm{errors}}{=}\left\{{"A"}\right\}{,}{\mathrm{trend}}{=}\left\{{"A"}\right\}{,}{\mathrm{seasonal}}{=}\left\{{"N"}\right\}{,}{\mathrm{α}}{=}{0.999874595856735}{,}{\mathrm{β}}{=}{0.21767056094623732}{,}{\mathrm{γ}}{=}{0.}{,}{\mathrm{φ}}{=}{1.}{,}{\mathrm{period}}{=}{1}{,}{\mathrm{l0}}{=}{17.560517881315064}{,}{\mathrm{b0}}{=}{0.34996342676412867}{,}{s}{=}\left(\left[\begin{array}{c}0.0\end{array}\right]\right){,}{\mathrm{σ}}{=}{0.06813734732902783}{,}{\mathrm{constraints}}{=}{"both"}\right)$ (5)
 > $\mathrm{fc}≔\mathrm{Forecast}\left(\mathrm{esm},20,\mathrm{output}=\mathrm{confidenceintervals}\left(95\right)\right)$
 ${\mathrm{fc}}{≔}\left[\begin{array}{c}{\mathrm{Time series}}\\ {\mathrm{VALUE \left(forecast - 2 percentile\right), VALUE \left(forecast - 50 percentile\right), VALUE \left(forecast - 98 percentile\right)}}\\ {\mathrm{20 rows of data:}}\\ {\mathrm{2012-12-30 - 2031-12-30}}\end{array}\right]$ (6)
 > $\mathrm{TimeSeriesPlot}\left(\mathrm{fc},\mathrm{ref}\right)$

 > 

Compatibility

 • The DataSets[Quandl][Reference] command was introduced in Maple 2015.
 • For more information on Maple 2015 changes, see Updates in Maple 2015.