gpscsv − dump the JSON output from gpsd as CSV
gpscsv [OPTIONS] [host[:port[:device]]]
gpscsv −h
gpscsv −V
gpscsv is a simple Python program for reading gpsd JSON data streams and outputting them in Comma Separated Values (CSV) format. It takes input from a specified gpsd and reports to standard output. The program runs until the gpsd dies, "−n COUNT" messages are processed, "−x SECONDS" have passed, or it is interrupted by ˆC or other means.
gpscsv can only collect data that your gpsd is already sending. Use gpspipe to see what JSON message classes it is sending.
One good use of gpscsv is to create CSV files for use with the gnuplot program.
gpscsv does not need root, but will run fine as root.
The program accepts the following options:
−?, −h, −−help
Show help information and exit.
−c MCLASS, −−class MCLASS
Select the JSON class messages of type MCLASS. Overrides the default class of TPV. See the CLASSES section below for more information.
−−cvt−isotime
Convert fields named "time" from ISO time to UNIX time.
−D LVL, −−debug LVL
Set debug level to LVL. Default 0. Higher arguments than 0 produce more debug output.
−−device DEVICE
The DEVICE on the gpsd to connect to. Defaults to all.
−f FIELDS, −fields FIELDS
The FIELDS from the JSON message to dump to the output. Set FIELD to empty ('') for all initially seen fields. Default varies by CLASS.
−−file FILE
Read JSON from FILE instead of from gpsd.
−−header HEADER
Set header style to HEADER. 0 for no header, 1 output fields as header, 2 send fields as a comment ('#'). Defaults to 1.
−−host HOST
Connect to the gpsd on HOST. Defaults to localhost.
−n COUNT, −−count COUNT
Exit after outputting COUNT records. Set COUNT to 0 to disable. Default is 0
−−port PORT
Use PORT to connect to gpsd. Defaults to 2947.
−−separator SEPARATOR
Use SEPARATOR as the field separator. Default separator is a comma (',').
−V, −−version
Show gpscsv version, and exit.
−x SECONDS, −−seconds SECONDS
Exit after SECONDS number of seconds have passed. Set SECONDS to 0 to disable. Default is 0
All the above individual options may be specified multiple times, but t only the last one off each will be used.
Some of the gpsd JSON message classes include sub−classes. gpscsv allows direct access to them using a meta−class (MCLASS).
By default, clients collect data from the local gpsd daemon running on localhost, using the default GPSD port 2947. The optional argument to any client may override this behavior: [server[:port[:device]]]
For further explanation, and examples, see the ARGUMENTS section in the gps(1) man page
Some basic standalone examples:
Grab three cycles of TPV data:
$ gpscsv
−c TPV −n 3
time,lat,lon,altHAE
2021−07−28T22:38:37.000Z,44.0688638,−121.3140643,1108.223
2021−07−26T22:38:37.000Z,44.068863833,−121.314064333,1108.3
2021−07−28T22:38:38.000Z,44.0688637,−121.314065,1108.363
Grab one set of satellite data:
$ gpscsv
−c SAT −n 1
time,gnssid,svid,PRN,az,el,ss,used,health
2021−07−28T22:37:46.000Z,0,8,8,311.0,28.0,33.0,True,1
2021−07−28T22:37:46.000Z,0,10,10,290.0,74.0,50.0,True,1
2021−07−28T22:37:46.000Z,0,15,15,45.0,18.0,31.0,False,1
2021−07−28T22:37:46.000Z,0,16,16,244.0,7.0,23.0,True,1
2021−07−28T22:37:46.000Z,0,18,18,109.0,43.0,37.0,True,1
2021−07−28T22:37:46.000Z,0,23,23,49.0,62.0,38.0,True,1
2021−07−28T22:37:46.000Z,0,24,24,87.0,16.0,28.0,True,1
2021−07−28T22:37:46.000Z,0,27,27,280.0,52.0,42.0,True,1
2021−07−28T22:37:46.000Z,0,32,32,188.0,32.0,42.0,True,1
2021−07−28T22:37:46.000Z,5,3,195,305.0,6.0,13.0,False,1
2021−07−28T22:37:46.000Z,6,2,66,38.0,8.0,21.0,False,1
2021−07−28T22:37:46.000Z,6,3,67,34.0,60.0,32.0,True,1
2021−07−28T22:37:46.000Z,6,4,68,226.0,63.0,34.0,True,1
2021−07−28T22:37:46.000Z,6,5,69,220.0,12.0,32.0,True,1
2021−07−28T22:37:46.000Z,6,11,75,−999,4.0,0.0,False,2
2021−07−28T22:37:46.000Z,6,12,76,47.0,0.0,0.0,False,1
2021−07−28T22:37:46.000Z,6,17,81,142.0,8.0,31.0,True,1
2021−07−28T22:37:46.000Z,6,18,82,138.0,57.0,40.0,True,1
2021−07−28T22:37:46.000Z,6,19,83,333.0,70.0,29.0,True,1
2021−07−28T22:37:46.000Z,6,20,84,323.0,10.0,0.0,False,1
Some plot examples, do them in exact order shown:
Grab 100 samples of time,lat,lon,altHAE:
$ gpscsv −n 100 −−cvt−isotime > tpv.dat
Grab 100 samples of time,epx,epy,epv,eph,sep
$ gpscsv −n 100 −−cvt−isotime −f time,epx,epy,epv,eph,sep > ep.dat
Grab 100 samples of time,xdop,ydop,vdop,tdop,hdop,gdop,pdop
$ gpscsv −n 100 −−cvt−isotime −c SKY > sky.dat
Grab 100 samples of time,nSat,uSat
$ gpscsv −n 100 −−cvt−isotime −c SKY −f time,nSat,uSat > sat.dat
Start gnuplot in interactive mode:
$ gnuplot
Some gnuplot housekeeping:
# this are csv
files
gnuplot> set datafile separator ','
# use the first line as title
gnuplot> set key autotitle columnhead
# X axis is UNIT time in seconds.
gnuplot> set xdata time
gnuplot> set timefmt "%s"
Now to plot time vs latitude, using tpv.dat from above:
gnuplot> plot 'tpv.dat' using 1:2
Then to plot longitude and altHAE, in separate plots:
gnuplot>
plot 'tpv.dat' using 1:3
gnuplot> plot 'tpv.dat' using 1:4
Put both latitude and longitude on one plot:
gnuplot> set
y2tics
gnuplot> plot 'tpv.dat' using 1:2, '' using 1:3 axes
x1y2
Plot epx, epy, epv, eph, and sep in one plot, using ep.dat from above:
gnuplot>
plot 'ep.dat' using 1:2, '' using 1:3, \
'' using 1:4, '' using 1:5, '' using 1:6
Plot all the DOPs on one plot, from sky.dat above:
gnuplot>
plot 'sky.dat' using 1:2, '' using 1:3, '' using 1:4, \
'' using 1:5, '' using 1:6, '' using 1:7, '' using 1:8
Plot nSat and uSat together:
gnuplot> plot 'sat.dat' using 1:2, '' using 1:3
Lat/lon scatter plot:
# x is no
longer time
gnuplot> set xdata
gnuplot> plot 'tpv.dat' using 3:2 title 'fix'
0
on success.
1
on failure
gpspipe(1), gpsd_json(5), gpsd(8), gnuplot(1)
Project web site: <https://gpsd.io/>
This file is
Copyright 2020 by the GPSD project
SPDX−License−Identifier:
BSD−2−clause
Gary E. Miller