National Oceanic and Atmospheric Administration (NOAA), National Environmental Satellite, Data, and Information Service(NESDIS)

Global Monthly AVHRR Climatology Over Land
Clear-sky top-of-the-atmosphere variables


by Garik Gutman, Dan Tarpley, Aleksandr Ignatov, NOAA/NESDIS Satellite Research Laboratory, Camp Springs, Maryland
and Steve Olson, Research and Data Systems Corporation, Greenbelt, Maryland.
This is Volume 3 in the Global Change Data Base:
Editor David Hastings, NOAA/NESDIS National Geophysical Data Center, Boulder, Colorado


This is the aareadme.htm file in directory: /data/vector/idrisi
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The data contained here are vector files for coasts, islands, nations, states, rivers, lakes, and states in IDRISI ASCII vector file format.

The data are from Micro World Data Bank II (see accompanying documentation in the \DOCUMENT\VECTOR directory).

The subdirectory IDRISDVC contains IDRISI vector header files.

IDRISI's ASCII vector file format is relatively simple, making the data relatively easy to convert to an ASCII import format for most vector geographic information systems. Indeed, some GISs have importation routines for IDRISI, making the conversion even easier.

A typical line segment has the following format:

  • F1 M F1 is a feature identifier for line segment 1 M is the
  • X1 Y1 number of X,Y (longitude,latitude) pairs that describe
  • X2 Y2 points, or vertices, in the line segment.

  • XM YM XM is the X value, and YM is the Y value, of the Mth point in the line segment.
  • F2 N F2 is the feature identifier for line segment 2, etc.
  • X1 Y1
  • XN YN

    0 0 This marks the end of an IDRISI ASCII vector file. This directory contains binary vector files in GRASS4.X format.

    file:./aareadme.htm
    Revised: 10 March 1997