NAME

       mgd77header - Generate MGD77 header from data records

SYNOPSIS

       mgd77header NGDC-id.a77 [ -Hheadervalues.txt ] [ -Mf|r ] [ -V ]

DESCRIPTION

       mgd77header  generates  an MGD77 header by reading A77 data (i.e., the data record portion
       of MGD77 files), determines temporal and spatial extents, ten degree  boxes  crossed,  and
       data  columns  present.  Optionally,  it  can also read an input file consisting of header
       field values (-H) to be included in program output. Header field  values  determined  from
       data and read from input are output in either MGD77 format (f) or as a list (r) (-M).

OPTIONS

       No space between the option flag and the associated arguments.

       -H     Obtain  header  field  values  from  an input text file. Each row of the input file
              should consist of a header field name and its desired value, separated by a  space.
              See below for a sample header file and for the full list of header field names.

       -M     Choose between MGD77 formatted header output f or list r.

       -V     Selects  verbose  mode,  which  will  send progress reports to stderr [Default runs
              "silently"].

Header Item Sample File:

       Format_Acronym MGD77
       Source_Institution SOEST - UNIV. OF HAWAII
       Country USA
       Platform_Name KILO MOANA
       Platform_Type_Code 1
       Platform_Type SHIP

Names of All MGD77 Header Fields

       Survey_Identifier
       Format_Acronym
       Data_Center_File_Number
       Parameters_Surveyed_Code
       File_Creation_Year
       File_Creation_Month
       File_Creation_Day
       Source_Institution
       Country
       Platform_Name
       Platform_Type_Code
       Platform_Type
       Chief_Scientist
       Project_Cruise_Leg
       Funding
       Survey_Departure_Year
       Survey_Departure_Month
       Survey_Departure_Day
       Port_of_Departure
       Survey_Arrival_Year
       Survey_Arrival_Month
       Survey_Arrival_Day
       Port_of_Arrival
       Navigation_Instrumentation
       Geodetic_Datum_Position_Determination_Method
       Bathymetry_Instrumentation
       Bathymetry_Add_Forms_of_Data
       Magnetics_Instrumentation
       Magnetics_Add_Forms_of_Data
       Gravity_Instrumentation
       Gravity_Add_Forms_of_Data
       Seismic_Instrumentation
       Seismic_Data_Formats
       Format_Type
       Format_Description
       Topmost_Latitude
       Bottommost_Latitude
       Leftmost_Longitude
       Rightmost_Longitude
       Bathymetry_Digitizing_Rate
       Bathymetry_Sampling_Rate
       Bathymetry_Assumed_Sound_Velocity
       Bathymetry_Datum_Code
       Bathymetry_Interpolation_Scheme
       Magnetics_Digitizing_Rate
       Magnetics_Sampling_Rate
       Magnetics_Sensor_Tow_Distance
       Magnetics_Sensor_Depth
       Magnetics_Sensor_Separation
       Magnetics_Ref_Field_Code
       Magnetics_Ref_Field
       Magnetics_Method_Applying_Res_Field
       Gravity_Digitizing_Rate
       Gravity_Sampling_Rate
       Gravity_Theoretical_Formula_Code
       Gravity_Theoretical_Formula
       Gravity_Reference_System_Code
       Gravity_Reference_System
       Gravity_Corrections_Applied
       Gravity_Departure_Base_Station
       Gravity_Departure_Base_Station_Name
       Gravity_Arrival_Base_Station
       Gravity_Arrival_Base_Station_Name
       Number_of_Ten_Degree_Identifiers
       Ten_Degree_Identifier
       Additional_Documentation_1
       Additional_Documentation_2
       Additional_Documentation_3
       Additional_Documentation_4
       Additional_Documentation_5
       Additional_Documentation_6
       Additional_Documentation_7

EXAMPLES

       To generate an MGD77 header from A77 input, try

       mgd77header km0201 -H kmheaderitems.txt -Mf > km0201.h77

SEE ALSO

       mgd77list(1), mgd77manage(1), mgd77path(1), mgd77track(1) x2sys_init(1)

REFERENCES

       Wessel, P., and W. H. F. Smith, 2013, The  Generic  Mapping  Tools  (GMT)  version  4.5.11
       Technical Reference & Cookbook, SOEST/NOAA.
       Wessel,  P.,  and  W.  H.  F.  Smith, 1998, New, Improved Version of Generic Mapping Tools
       Released, EOS Trans., AGU, 79 (47), p. 579.
       Wessel, P., and W. H. F. Smith, 1995, New Version of the Generic Mapping  Tools  Released,
       EOS Trans., AGU, 76 (33), p. 329.
       Wessel,  P.,  and W. H. F. Smith, 1995, New Version of the Generic Mapping Tools Released,
       http://www.agu.org/eos_elec/95154e.html, Copyright 1995 by the American Geophysical Union.
       Wessel, P., and W. H. F. Smith, 1991, Free  Software  Helps  Map  and  Display  Data,  EOS
       Trans., AGU, 72 (41), p. 441.
       The     Marine     Geophysical     Data     Exchange     Format     -     "MGD77",     see
       http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.txt