This function transforms the coordinates of spline data between Cartesian and polar coordinate systems. The origin x and y coordinates can be supplied by the user, or calculated automatically (see Details).
transform_coord(
data,
to = "polar",
origin = NULL,
fan_lines = c(10, 25),
use_XY = FALSE
)A data set containing the spline coordinates (cartesian coordinates must be in columns named X and Y, polar coordinates in columns named angle and radius; these are the defaults in data imported with read_aaa()).
Which system to convert to, as a string, either "polar" or "cartesian" (the default is "polar").
The coordinates of the origin as a vector of c(x, y) coordinates.
A numeric vector with two fan lines (the default is
c(10, 25)).
Whether to use the column names X and Y when converting to and from polar coordinates, rather than the default angle and radius (the default is FALSE. If TRUE, the columns X and Y are overwritten with the converted values. If converting to polar, X is the angle and Y the radius.
An object of class tbl_df-class (a tibble).
The transformation between the coordinate systems require the selection of an
origin in Cartesian coordinates (x and y). The origin ideally corresponds to
the virtual origin of the ultrasound waves from the probe. The origin
coordinates can be supplied by the user as a vector with the origin
argument, or they can be estimated automatically if origin = NULL (the
default). The estimation is performed by get_origin (see that
function documentation for details).