conversion : procedure; specifies a procedure to be mapped onto the elements in the given data series. This option is entered in the form conversion = procedure.

The SubsDatatype command changes the datatype of the entries in a DataSeries as well as the indicated datatype of the data series.

If the conversion option is given, then the values in the DataSeries are converted by this conversion procedure. Otherwise, they are typically not modified, but there are exceptions. Internally, a new Array is constructed with the given datatype, and the current values are used to initialize this Array; this is the step where an automatic conversion could take place.

$\mathrm{genus}≔\mathrm{DataSeries}\left(⟨''Rubus''\,''Vitis''\,''Fragaria''⟩\,\mathrm{labels}=\left[\mathrm{Raspberry}\,\mathrm{Grape}\,\mathrm{Strawberry}\right]\,\mathrm{datatype}=\mathrm{string}\right)\:$

$\mathrm{energy}≔\mathrm{DataSeries}\left(⟨220\,288\,136⟩\,\mathrm{labels}=\left[\mathrm{Raspberry}\,\mathrm{Grape}\,\mathrm{Strawberry}\right]\,\mathrm{datatype}=\mathrm{integer}\right)\:$

$\mathrm{carbohydrates}≔\mathrm{DataSeries}\left(⟨11.94\,18.1\,7.68⟩\,\mathrm{labels}=\left[\mathrm{Raspberry}\,\mathrm{Grape}\,\mathrm{Strawberry}\right]\,\mathrm{datatype}=\mathrm{float}\right)\:$

$\mathrm{top\_producer}≔\mathrm{DataSeries}\left(⟨\mathrm{Russia}\,\mathrm{China}\,\mathrm{USA}⟩\,\mathrm{labels}=\left[\mathrm{Raspberry}\,\mathrm{Grape}\,\mathrm{Strawberry}\right]\,\mathrm{datatype}=\mathrm{name}\right)\:$

$\mathrm{berries}≔\mathrm{DataFrame}\left(\mathrm{Energy}=\mathrm{energy}\,\mathrm{Carbohydrates}=\mathrm{carbohydrates}\,\mathrm{TopProducer}=\mathrm{top\_producer}\,\mathrm{Genus}=\mathrm{genus}\right)$

$\mathrm{berries}≔\left[\begin{array}{ccccc}& \mathrm{Energy}& \mathrm{Carbohydrates}& \mathrm{TopProducer}& \mathrm{Genus}\\ \mathrm{Raspberry}& 220& 11.9400000000000& \mathrm{Russia}& ''Rubus''\\ \mathrm{Grape}& 288& 18.1000000000000& \mathrm{China}& ''Vitis''\\ \mathrm{Strawberry}& 136& 7.68000000000000& \mathrm{USA}& ''Fragaria''\end{array}\right]$

$\mathrm{Datatypes}\left(\mathrm{berries}\right)$

$\left[\mathrm{integer}\,{\mathrm{float}}_8\,\mathrm{name}\,\mathrm{string}\right]$

$\mathrm{Datatype}\left(\mathrm{carbohydrates}\right)$

${\mathrm{float}}_8$

$\mathrm{SubsDatatype}\left(\mathrm{energy}\,\mathrm{float}\right)$

$\left[\begin{array}{cc}\mathrm{Raspberry}& 220.\\ \mathrm{Grape}& 288.\\ \mathrm{Strawberry}& 136.\end{array}\right]$

$\mathrm{energy}≔\mathrm{SubsDatatype}\left(\mathrm{energy}\,\mathrm{float}\right)$

$\mathrm{energy}≔\left[\begin{array}{cc}\mathrm{Raspberry}& 220.\\ \mathrm{Grape}& 288.\\ \mathrm{Strawberry}& 136.\end{array}\right]$

$\mathrm{Datatype}\left(\mathrm{energy}\right)$

${\mathrm{float}}_8$

$\mathrm{genus}≔\mathrm{SubsDatatype}\left(\mathrm{genus}\,\mathrm{name}\,\mathrm{`=`}\left(\mathrm{conversion}\,x\mapsto \mathrm{convert}\left(x\,\mathrm{name}\right)\right)\right)$

$\mathrm{genus}≔\left[\begin{array}{cc}\mathrm{Raspberry}& \mathrm{Rubus}\\ \mathrm{Grape}& \mathrm{Vitis}\\ \mathrm{Strawberry}& \mathrm{Fragaria}\end{array}\right]$

$\mathrm{Datatype}\left(\mathrm{genus}\right)$

$\mathrm{name}$

$\mathrm{top\_producer}≔\mathrm{SubsDatatype}\left(\mathrm{top\_producer}\,\mathrm{string}\,\mathrm{`=`}\left(\mathrm{conversion}\,x\mapsto \mathrm{convert}\left(x\,\mathrm{string}\right)\right)\right)$

$\mathrm{top\_producer}≔\left[\begin{array}{cc}\mathrm{Raspberry}& ''Russia''\\ \mathrm{Grape}& ''China''\\ \mathrm{Strawberry}& ''USA''\end{array}\right]$

$\mathrm{Datatype}\left(\mathrm{top\_producer}\right)$

$\mathrm{string}$

$\mathrm{berries}≔\mathrm{DataFrame}\left(\mathrm{Energy}=\mathrm{energy}\,\mathrm{Carbohydrates}=\mathrm{carbohydrates}\,\mathrm{TopProducer}=\mathrm{top\_producer}\,\mathrm{Genus}=\mathrm{genus}\right)$

$\mathrm{berries}≔\left[\begin{array}{ccccc}& \mathrm{Energy}& \mathrm{Carbohydrates}& \mathrm{TopProducer}& \mathrm{Genus}\\ \mathrm{Raspberry}& 220.& 11.9400000000000& ''Russia''& \mathrm{Rubus}\\ \mathrm{Grape}& 288.& 18.1000000000000& ''China''& \mathrm{Vitis}\\ \mathrm{Strawberry}& 136.& 7.68000000000000& ''USA''& \mathrm{Fragaria}\end{array}\right]$

$\mathrm{Datatypes}\left(\mathrm{berries}\right)$

$\left[{\mathrm{float}}_8\,{\mathrm{float}}_8\,\mathrm{string}\,\mathrm{name}\right]$

The DataSeries/SubsDatatype command was introduced in Maple 2017.

For more information on Maple 2017 changes, see Updates in Maple 2017.