NAME

USAGE

DESCRIPTION

The fextract-events task does basic event filtering. It could be considered a stripped down version of 'extractor' which does only event filtering (no images, spectra or light curves), but it does it many times faster.

fextract-events can perform temporal or spatial filtering using good time interval files (GTIs) and/or spatial region files, respectively. Also, basic column filtering by command-line interval ranges are supported as in 'extractor'.

fextract-events does not accept all the parameters of extractor (in particular, not the spectrum, light curve, or image parameters), but the event filtering parameters are accepted, and have the same names.

Time filtering is performed by using GTIs. The GTIs from all the input 'timefile's (if any) are ORed together; the GTIs from all the input event files are ORed together; and then finally, these two sets are ANDed together to form the master time filter.

PARAMETERS

filename [string]

The input event filename. If this starts with "@" then it is assumed to be an ascii file containing a list of event files to be read. Interval filters can be specified by appending them inside [] on the end of this parameter. For instance, to accept only events with PHA lying between 7 and 30 the filename will be specified by "infile.evt[pha=7:30]". If a list of filenames is given (using "@") then the interval filtering should be specified on the input paramater, not on the individual event filenames. Successive interval filters should be separated by spaces or commas. Interval filters must correspond to a column name in the input event file.

eventsout

The name for the output events file.

(regionfile = "NONE") [string]

The name of a spatial region file, or NONE for no spatial filtering. The region coordinates are assumed to be given by the xcolf and ycolf parameters.

(timefile = "NONE") [string]

The name of a temporal good time interval file, or NONE for no temporal filtering. Note that there is no 'gtinam' parameter; you should specify the extension name directly in the timefile parameter, for example as "timefile='mytime.gti[STDGTI]'".

(xcolf = "DETX") [string]

The name of the column used for the X coordinate when region filtering.

(ycolf = "DETY") [string]

The name of the column used for the Y coordinate when region filtering.

(tcol = "TIME") [string]

The name of the column used for the time of the event.

(events = "EVENTS") [string]

The name of the EVENTS extension in the input files.

(gti = "STDGTI") [string]

The name of the GTI extension in the input event files.

(copyall = NO) [boolean]

Not currently used.

(clobber = NO) [boolean]

If the output file already exists, then setting "clobber = yes" will cause it to be overwritten.

(chatter = 2) [integer, 0 - 5]

Amount of verbosity of the task. For chatter=0, no output is printed. For chatter=5, debugging output is printed.

(history = YES) [boolean]

If history = YES, then a set of HISTORY keywords will be written to the header of the specified HDU in the output file to record the value of all the task parameters that were used to produce the output file.

EXAMPLES

1. Perform filtering on theevent files listed in the ASCI file infile.lis. The temporal filters listed in the GTI file select.gti, and the spatial filters listed in the region file select.reg are applied. The output is sent to output.evt.

  fextract-events @infile.lis output.evt timefile=select.gti regionfile=select.reg

SEE ALSO

extractor