Select a subset of rows of a data set to be retained

This function selects which rows of a data set should be included. Either the begin or the end argument need to be specified. The column does not need to be sorted for this function to work. Values are included if they are >= begin and <= end, if specified, for the specified column. Values that are NA are never removed by this function.

select_range(av_state, subset_id = 1, column, begin, end)

Arguments

av_state	an object of class av_state
subset_id	either an integer subset index or the the value for the id_field column that was used in the group_by function. The subset_id argument is required if the data set is grouped into multiple data sets (i.e., if the group_by function was used), in which case the function works on the specified data subset.
column	specifies which column the begin and end values should be taken over. This argument is optional, and if it is missing, id_field used in order_by will be used.
begin	indicates which values should be included. Values that are >= begin are included. This argument is optional if end is specified.
end	indicates which values should be included. Values that are <= end are included. This argument is optional if begin is specified.

Value

This function returns the modified av_state object.

Examples

# NOT RUN {
av_state <- load_file("../data/input/pp2 nieuw compleet_64dagen.sav",log_level=3)
av_state <- order_by(av_state,'tijdstip')
print(av_state)
av_state$data[[1]]['tijdstip']
# default column is the order_by column in this case:
av_state <- select_range(av_state,begin=20,end=40)
print(av_state)
av_state$data[[1]]['tijdstip']

av_state <- load_file("../data/input/pp2 nieuw compleet_64dagen.sav",log_level=3)
print(av_state)
av_state$data[[1]]['lnSomPHQ']
# now only retain rows with 0 <= lnSomPHQ <= 2
av_state <- select_range(av_state,column='lnSomPHQ',begin=0,end=2)
print(av_state)
av_state$data[[1]]['lnSomPHQ']
# }