MetFns (version 2.1.0)

filter.datetime: Selection of visual meteor data by date(s)

Description

Selects data for a given visual meteor dataset and specified year, month (s), day (s) and time period.

Usage

filter.datetime(data,year,month.beg,month.end=month.beg,day.beg,
day.end = day.beg,time.beg=0,time.end=2359)

Arguments

data

data frame consisting of visual meteor data (rate or magnitude data).

year

numeric vector of length 4 specifying year.

month.beg

numeric vector specifying the beginning month.

month.end

numeric vector specifying the ending month. By default, month.end is set to be equal to month.beg.

day.beg

numeric vector specifying the beginning day.

day.end

numeric vector specifying the ending day. By default, day.end is set to be equal to day.beg.

time.beg

numeric vector (0-2359) specifying lower boundary of time in hours and minutes, corresponding to day.beg. By default, time.beg is set to be equal to 0.

time.end

numeric vector(0-2359) specifying upper boundary of time in hours and minutes, corresponding to day.end. By default, time.end is set to be equal to 2359.

Value

filter.datetime returns data frame with the same number of columns as the argument data, containing observations which correspond to the specified time period.

Details

Day given in meteor datasets corresponds to the beginning of the observing time period. In selection of the data, day corresponding to the middle of the observing time period is used.

If argument day.end is not provided, the function filter.datetime selects data for a given date, otherwise it selects data for a period of days, bounded by day.beg and day.end, in one or more months, bounded by month.beg and month.end. Arguments time.beg and time.end correspond to day.beg and day.end, respectively. If they are provided, the middle of the observing time period is used in data selection.

Data selection is performed using filter.sol which filters data by solar longitudes corresponding to specified dates.

References

http://www.imo.net/data/visual

Rendtel J. and Arlt R., editors (2008). IMO Handbook For Meteor Observers. IMO, Potsdam.

See Also

filter, filter.sol

Examples

## select visual meteor data for the period from 5-15 August 2007

## rate data for the year 2007
data(rate07)
filter.datetime(rate07,year=2007,month.beg=8,day.beg=5,day.end=15)

## magnitude data for the year 2007
data(magn07)
filter.datetime(magn07,year=2007,month.beg=8,day.beg=5,day.end=15)

##select rate data for the period from 25 July 20h to 20 August, 3h
filter.datetime(rate07,year=2007,month.beg=7,month.end=8, day.beg=25,day.end=20,
time.beg=2000,time.end=300)