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Geomagnetic Utility Programs

NCEI provides access to 12 programs (described and referenced in Introduction to Geomagnetic Fields by Wallace Campbell(link is external)) that are designed to help users understand geomagnetic fields. These programs are all designed to operate in a DOS environment, with a few exceptions:

  • GEOMAG will run in a DOS window within a Windows PC environment, but will not execute in a pure 16-bit DOS environment
  • DSTDEMO may not execute from Windows 2000 DOS prompts

GMCORD, Day Number, POLYFIT, SORTVAL and ANALYZ are available in both Linux and Windows with C source code. A new program GMPOLE is also available in this fashion.

Disclaimer: These programs are intended as educational tools to help users understand geomagnetic fields, and are free to access and share without restriction. They are not guaranteed or intended for any other purpose. Neither NCEI nor the book publishers provide a warranty (expressed or implied), endorsement, guarantee of accuracy, or responsibility for the program's functioning. The executable programs (.exe) and all other necessary files must also be copied to the same directory for proper operation of the set.

Access

Note: Google and Mozilla have deprecated support for FTP server access on Chrome and Firefox. Review the documentation to learn about FTP access options.

FTP Documentation

Geomagnetic Field Programs
Program Name Description Download Options
ANALYZ Mean, Standard Deviation, and Correlation | ANALYZ Documentation
APEX A file processing program for geomagnetic coordinate transformation | APEX Documentation
Day Number Determines the number of the day in the year | Day Number Documentation
DSTDEMO Geomagnetic Disturbance Index, demonstration of spherical harmonics | DSTDEMO Documentation Program and data (ftp)
FOURSQ1 Computes the Fourier harmonic spectral components of quiet field records | FOURSQ1 Documentation Program (ftp)
GEOMAG Provides field values computed from the International Geomagnetic Reference Field (IGRF) model | IGRF Fields Documentation Program and data (ftp)
GMCORD Performs coordinate transformation from Geodetic to Geomagnetic coordinates | GMCORD Documentation
GMPOLE Location of the North Geomagnetic Pole | GMPOLE Documentation
IGRF Field Models A table of all the spherical harmonic Gauss coefficients, g and h, of the International Geomagnetic Reference Fields (IGRF) and Definitive Geomagnetic Reference Fields (DGRF) for 1900–2005. | IGRF Model Fields Documentation Table (ftp)
POLYFIT Creates a polynomial equation portrayal of data points | POLYFIT Documentation
SORTVAL Median of sorted values | SORTVAL Documentation
SPH Graphical demonstration of Spherical Harmonics | SPH Documentation Program (ftp)
SQ1MODEL Quiet-Day Field Variation, Sq | SQU1MODEL Documentation Program (ftp) 
SUN-MOON Location of the Sun and Moon | SUN-MOON Documentation Program (ftp)
Utility C Programs  A package of all the new C utility programs