Changes between Version 6 and Version 7 of Cf2CrsWkt


Ignore:
Timestamp:
10/10/12 13:59:49 (7 years ago)
Author:
etourigny
Comment:

--

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  • Cf2CrsWkt

    v6 v7  
    165165||||||false_northing||false_northing||+y_0||False northing||8807||!FalseNorthing||||
    166166
    167 === '''Notes:''' ===
     167=== '''Table Notes:''' ===
    168168
    169169 1. Multiple CF/WKT translations, see projection-specific translations.
    170170 2. Parameter used in every projection.
    171171 3. See projection-specific notes.
     172
     173=== Units Information ===
     174
     175Translation of units depends on if the crs is geographic or projected
     176
     177For a geographic crs (grid_mapping_name = "latitude_longitude"), units are angular. GEOGCS contains a UNIT node which gives the conversion to radians. When the crs is in degrees the following node is used: UNIT["degree",0.0174532925199433]. For a more complete description, see CT 1.0 section "7.3.19 UNIT"
     178CF requires all value to be in degrees, which is specified in the dimension's units attribute ( lon:units = "degrees_east" / lat:units = "degrees_north" ), the udunits packages allows to transform from radians.
     179
     180For a projected crs, units are linear.  PROJCS must contains a UNIT node which gives the conversion into meters. For example, if the units are in kilometers the following node is used: UNIT["kilometre",1000]].
     181In CF, units are given in the dimension's units attribute (xc:units = "m").
    172182
    173183=== Projection-specific notes ===