You can do this easily with the software FERRET (
I've attached a FERRET script which computes the number of strikes for a
given area. You can run it from the UNIX/LINUX command line, e.g.
ferret -nojnl -script count_strikes.jnl 20060320_0500.nc testout.txt 30
30.1 -180 180
Best regards, Ingo
Has anyone written software that will perform the following?
1. Will input netCDF-formatted files containing point (instead of
gridded) data. The data in my case is lightning. Attached is an
example of the netCDF file.
2. Will perform either of the following:
(a) Allow me to input a location in latitude/longitude space and
determine whether or not any of the lightning strikes (from data
contained within the netCDF file) are within X km of the input location.
(b) Allow me to use latitude/longitude values to define a box in
horizontal space, then determines whether or not any of the lightning
strikes (from data contained within the netCDF file) are within the box.
The software needs to be of command-line type (no GUIs) that operates
in a Linux environment.
! DESCRIPTION: counts strikes in a given area
\cancel mode verify
! process input arguments
define symbol infile=$1
define symbol outfile=$2
define symbol latmin=$3
define symbol latmax=$4
define symbol lonmin=$5
define symbol lonmax=$6
! open input file
! count strikes
let mask=if (lon ge ($lonmin) and lon le ($lonmax) \
and lat ge ($latmin) and lat le ($latmax)) then 1 else 0
let /title="Number of strikes in ($latmin)N to ($latmax)N and ($lonmin)E to
! write result to display
! write result to file
list /clobber /nohead /file=($outfile) nstrikes