This function creates a SurvData object from experimental data
provided as a data.frame. The resulting object
can then be used for plotting and model fitting. It can also be used
to generate individual-time estimates.
The x argument describes experimental results from a survival
toxicity test. Each line of the data.frame
corresponds to one experimental measurement, that is a number of alive
individuals at a given concentration at a given time point and in a given replicate.
Note that either the concentration
or the number of alive individuals may be missing. The data set is inferred
to be under constant exposure if the concentration is constant for each
replicate and systematically available. The function survData fails if
x does not meet the
expected requirements. Please run survDataCheck to ensure
x is well-formed.
survData(data, ...)# S3 method for data.frame
survData(data, ...)
A dataframe of class survData and column replicate as factor.
a data.frame containing the following four columns:
replicate: a vector of any class numeric, character or factor for replicate
identification. A given replicate value should identify the same group of
individuals followed in time
conc: a vector of class numeric with tested concentrations
(positive values, may contain NAs)
time: a vector of class integer with time points, minimal value must be 0
Nsurv: a vector of class integer providing the number of
alive individuals at each time point for each concentration and each replicate
(may contain NAs)
Further arguments to be passed to generic methods
survDataCheck