c3d_convert {c3dr}R Documentation

Convert between c3d point data formats

Description

Convert between different representations of point data in c3d files.

Usage

c3d_convert(data, format)

Arguments

data

A data frame of class c3d_data as generated by c3d_data(). The data can have any of the three data formats (see Data Formats section below).

format

Either "wide" (default), "long", or "longest" to determine the format of the resulting data frame. See the Data Formats section for more details.

Value

A data frame of class c3d_data in the format specified by the format argument.

Data Formats

Wide

The wide format has three numeric columns per point (x, y, z). The column names have the structure pointname_type, so for example the x-coordinate of a point named C7 has the name C7_x. Each row corresponds to one recording frame.

Long

The long format has one column per point. The column names correspond to the names of the points. Each recording frame corresponds to three rows of data (x, y, z). In additional to the point columns containing numeric data there are two additional columns: One that indicates the frame number (frame, numeric) and one that indicates the coordinate type (type, either x, y, or z, as a character).

Longest

The longest format has one data column (value, numeric). The other columns indicate the frame number (frame, numeric), the coordinate type (type, either x, y, or z, as a character), and the point name (point, character). Thus, each row of the data frame corresponds to one data entry.

Examples

# Import example data
d <- c3d_read(c3d_example())
# get point data in wide format
w <- c3d_data(d, format = "wide")
# convert to long data
l <- c3d_convert(w, "long")
head(l)

[Package c3dr version 0.1.5 Index]