igrfeval

Syntax

igrfeval --help
igrfeval [-m] [-lat lat] [-lon lon] [-alt alt] [-fmt format]
igrfeval [-m] [-f filename] [-fmt format]

Synopsis

Calculate IGRF magnetic field components and magnitude [nT].

Options

`--help`	print the help message and exit.
`--version`	print the RST version number and exit.
`-m`	location is in geomagnetic rather than geographic coordinates.
`-lat lat`	calculate for the latitude lat.
`-lon lon`	calculate for the longitude lon.
`-alt alt`	calculate for the altitude in kilometers, alt.
`-re Re`	calculate for the Earth radius in kilometers, Re.
`-d yyyymmdd`	calculate for the date yyyymmdd (v2 only).
`-t hr:mn`	calculate for the time hr:mn (v2 only).
`-fmt format`	use the string fmt, to format the output.
`-xyz`	Output should be in Cartesian rather than North/East/Down coordinates.
`-f filename`	read a sequence of latitudes, longitudes and altitudes from the ASCII file, filename.
`-old_aacgm`	use old AACGM coordinates rather than v2.

Description

Calculates IGRF magnetic field components and magnitude in units of nanotesla [nT]. The output is written to standard output using the formatting string given by the "-fmt" option. The format string should be in the same format as that used by the printf function and will take two double precision floating point numbers as arguments.

If the "-f" option is given, the latitude,longitude and altitude are read from a space separated ASCII file. If the filename is "-" input is read from standard input.

Examples

igrfeval -lat 85.4 -lon 32.4 -alt 300.0

Calculate the IGRF magnetic field components at the coordinate given by latitude of 85.4 degrees, longitude 32.4 degrees and altitude of 300 kilometers.

igrfeval -m -f aacgm.txt

Calculate the IGRF magnetic field components for the geomagnetic coordinates in the file "aacgm.txt".