SWC - perl program for downloading waveform data from the NCEDC
The NCEDC is pleased to announce the introduction of the Simple Waveform Client (SWC), a command-line program for easily dowloading waveform retrieval from the NCEDC Archive and NCEDC DART (Data Available in Real Time). The NCEDC Simple Wave Client (SWC) and and companion program Simple Wave Server (SWS) at the NCEDC provide a simple interface for retrieving segments of continuous or event time series data in MiniSEED format. Data can be requested by SEED Station, Network, Channel, Location, time interval, and/or eventid.
SWC is a perl program and accomanying perl module that runs on Linux, Solaris/Unix, and MacOS systems. The NCEDC provides 2 Simple Wave Servers:
- an sws server for archived data in the NCEDC Data Archive,
- an sws server for real-time data in the NCEDC DART (Data Available in Real Time)
The swc program can be downloaded from the swc program directory. After downloading the distribution file, install the program with the following steps:
tar xvf swc-dist-108.tar cd swc-dist-108 perl INSTALL_SWC.plYou will be prompted for several options for personal vs system-wide installation.
The syntax for the swc program is shown below.
Syntax: swc [-h] [-M] [-T|-K] [-f starttime [ -t endtime | -s timespan ]] [-E eventid -D eventid_domain] [-o - | outputfile] [-e] [-d N] [-S server] [-H hostname ][-P port] sncl1 ... snclN where: -h Help - prints this help message. -I Request channel Inventory (menu list) instead of waveform data. -T|-K Trim waveforms to specified time (-T) or Keep data from records within specified time interval (-K). Default is -T. -f starttime Start time of waveform. The date and time are specified in a single string, and can can be provided in one of several formats: yyyy/mm/dd,hh:mm:ss.ffff yyyy.doy,hh:mm:ss.ffff The date must be fully specified. The time portion is optional, and may be specified to hour, minute, second, or subsecond resolution. -t endtime End time of waveform. -s timespan Timespan of request. Timespan is an integer string terminated with one of the following characters (case sensitive). If no terminater character is used, seconds are assumed. S = seconds d = days M = minutes m = months H = hours y = years -E eventid Specify an eventid for retrieving event waveforms. Not all Simple Waveform Servers support retrieval by event. The NCEDC DART does NOT know about events. -D event_domain Specify the domain for the eventid (NC or SC). -o - | outputfile Specifies an explicit output file, or '-' for stdout. If this option is not specified, an output file based on the SNCL and date_time will be created. -e Output event data into a directory
instead of the current directory. Does NOT override '-o' option. -S servername Generic name of waveform server. Valid servernames are: dart, ncedc_archive. Default servername is ncedc_archive. See .swc-init.pl file in home directory for configuration. -H hostname Explicit hostname or IP address of waveform server. -P portnumber Port number or port name of server. Default port number is 4999. -d N Debug value. Current values are: 1 = display request and response. sncl1 ... snclN A list of one or more SNCL-strings, each containing dot-separated sections: Station.Network.Channel.Location Each section may be a single component (eg BKS) or a comma-delimited list of components such as BKS,CMB or HHE,HHN,HHZ. If any section contains a comma-delimited list, the SNCL-string is expanded to multiple SNCLs by performing a cross-product of the each components the the section with every other other section of the SNCL-string. For blank location codes, you may optionally omit the .Location portion of the SNCL-string. Notes: 1. Wildcard characters used within a SNCL must be quoted to avoid having the Unix/Linux shell perform the wildcard expansion. For Unix/Linux, use a backslash character before the wildcard character, or enclose the SNCL string in quotes. Examples: 1. swc -S ncedc_archive -T -f 2010/02/24,05:15 -s 5M HOPS.BK.HHZ CMB.BK.HHZ 2. swc -S ncedc_archive -T -f 2010.123,12:05:15.67 -s 5M 'HOPS,CMB.BK.BHE,BHN,BHZ.*' expands to the list of SNCLs: HOPS.BK.BHE.* HOPS.BK.BHN.* HOPS.BK.BHE.* CMB.BK.BHE.* CMB.BK.BHN.* CMB.BK.BHE.* The waveform server will perform the wildcard expansion. 3. swc -S dart -T -f 2011.054,12:05:15.67 -s 5M 'CMB.BK.BHZ.*' 4. swc -S ncedc_archive -E 71365875 -e
The NCEDC is a joint project of the University of California, Berkeley and the USGS, with facilities located at the University of California, Berkeley. Please send us email at email@example.com or fill out our comments form if you have questions or comments about these changes.