An EventData object comprises a data frame with at least three fields named
Y; each row specifies an event that occurs
at a specific point.
PBSmapping functions that expect EventData will accept properly formatted data frames in their place (see 'Details').
as.EventData attempts to coerce a data frame to an object with
TRUE if its argument is of class
data frame to be coerced or tested.
Boolean value; if
Conceptually, an EventData object describes events (EID) that take place at specific points (X,Y) in two-dimensional space. Additional fields can specify measurements associated with these events. In a fishery context, EventData could describe fishing events associated with trawl tows, based on the fields:
EID - fishing event (tow) identification number;
Y - fishing location;
Duration - length of time for the tow;
Depth - average depth of the tow;
Catch - biomass captured.
Like PolyData, EventData can have attributes
zone, which may be absent. Inserting the string
"EventData" as the class attribute's first element alters the
behaviour of some functions, including
as.EventData method returns an object with classes
"data.frame", in that order.
Nicholas M. Boers, Associate Professor – Computer Science
MacEwan University, Edmonton AB
PolySet, PolyData, LocationSet
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.