18 `data.frame`

Disclaimer

These packages (Note 1) are a one-person project undergoing rapid evolution. Backward compatibility (per Hadley Wickham) is provided as a courtesy rather than a guarantee.

Until further notice, these packages should

not be used as a basis for research grant applications,
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In addition, work primarily based on these packages (Note 1) should not be presented at academic conferences or similar scholarly venues.

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The function data.frame() creates a data frame, i.e., an R object of S3 class 'data.frame'. Note 18.1 summarizes the S3 methods for the class 'data.frame' in the spatstat.* family of packages,

Note 18.1: S3 Methods for Class data.frame in spatstat.* Packages (Table 8.1)

`S3` methods `*.data.frame`
	visible	from	generic	isS4
`as.fv.data.frame`	TRUE	spatstat.explore	`spatstat.explore::as.fv`	FALSE
`as.hyperframe.data.frame`	TRUE	spatstat.geom	`spatstat.geom::as.hyperframe`	FALSE
`as.im.data.frame`	TRUE	spatstat.geom	`spatstat.geom::as.im`	FALSE
`as.owin.data.frame`	TRUE	spatstat.geom	`spatstat.geom::as.owin`	FALSE
`as.ppp.data.frame`	TRUE	spatstat.geom	`spatstat.geom::as.ppp`	FALSE
`as.psp.data.frame`	TRUE	spatstat.geom	`spatstat.geom::as.psp`	FALSE
`multiplicity.data.frame`	TRUE	spatstat.geom	`spatstat.geom::multiplicity`	FALSE
`uniquemap.data.frame`	TRUE	spatstat.univar	`spatstat.univar::uniquemap`	FALSE

Examples in Chapter 18 Require

library(groupedHyperframe)

18.1 Aggregate to (Grouped) Hyper Data Frame

The S3 generic function aggregate2hyper() aggregates an R object into a (grouped) hyper data frame. Package groupedHyperframe (v0.4.0, GPL-2) implements the following S3 methods (Table 18.1),

Table 18.1: S3 methods of groupedHyperframe::aggregate2hyper (v0.4.0)

	visible	isS4
`aggregate2hyper.data.frame`	FALSE	FALSE
`aggregate2hyper.groupedData`	FALSE	FALSE

The S3 method aggregate2hyper.data.frame() aggregates a data frame with substantial amount of duplicated information into a (grouped) hyper data frame.

In Chapter 2, Listing 2.1, Listing 2.2,

inspects the input data frame lung0 (Listing 2.1) by the user-specified (nested) grouping structure, e.g., image_id nested in patient_id;
identifies the input data frame column(s) with non-identical elements within the lowest group, e.g., the numeric column lung0$hladr and the factor column lung0$phenotype;
converts these column(s) into the hypercolumn(s) of the output grouped hyper data frame (Listing 2.2), e.g., the numeric-hypercolumn lung_g$hladr and the factor-hypercolumn lung_g$phenotype. Each row of the output grouped hyper data frame (Listing 2.2) represents the lowest group of the nested grouping structure.