Changes between Version 20 and Version 21 of NetCDF_ProjectionTestingStatus


Ignore:
Timestamp:
Jan 30, 2012, 11:54:20 AM (12 years ago)
Author:
etourigny
Comment:

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  • NetCDF_ProjectionTestingStatus

    v20 v21  
     1== CF-1.6 <--> WKT/PROJ.4 translation ==
     2
     3=== Parameter Table ===
     4
     5||'''Projection'''||'''Name'''||'''CF'''||'''OGC WKT'''||'''PROJ.4'''||'''EPSG'''||'''Note'''||
     6|| ||
     7||'''GEN'''||Generic||-||-||-||-|| ||
     8|| || ||scale_factor_at_projection_origin||scale_factor||k_0|| ||(1)||
     9|| || ||scale_factor_at_central_meridian||scale_factor||k_0|| ||(1)||
     10|| || ||standard_parallel![1]||standard_parallel_1||lat_1|| || ||
     11|| || ||standard_parallel![2]||standard_parallel_2||lat_2|| || ||
     12|| || ||longitude_of_central_meridian||longitude_of_center||lon_0|| ||(1)||
     13|| || ||longitude_of_central_meridian||central_meridian||lon_0|| ||(1)||
     14|| || ||longitude_of_projection_origin||longitude_of_center||lon_0|| ||(1)||
     15|| || ||longitude_of_projection_origin||central_meridian||lon_0|| ||(1)||
     16|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| ||(1)||
     17|| || ||latitude_of_projection_origin||latitude_of_center||lat_0|| ||(1)||
     18|| || ||straight_vertical_longitude_from_pole||central_meridian||lon_0|| ||(1)||
     19|| || ||false_easting||false_easting||x_0||(2)|| ||
     20|| || ||false_northing||false_northing||y_0||(2)|| ||
     21|| ||
     22||'''AEA'''||Albers Equal Area||albers_conical_equal_area||Albers_Conic_Equal_Area||aea||9822|| ||
     23|| || ||standard_parallel![1]||standard_parallel_1||lat_1|| || ||
     24|| || ||standard_parallel![2]||standard_parallel_2||lat_2|| || ||
     25|| || ||longitude_of_central_meridian||longitude_of_center||lon_0|| || ||
     26|| || ||latitude_of_projection_origin||latitude_of_center||lat_0|| || ||
     27|| ||
     28||'''AE'''||Azimuthal equidistant||azimuthal_equidistant||Azimuthal_Equidistant||aeqd||9832|| ||
     29|| || ||longitude_of_projection_origin||longitude_of_center||lon_0|| || ||
     30|| || ||latitude_of_projection_origin||latitude_of_center||lat_0|| || ||
     31|| ||
     32||'''LAEA'''||Lambert azimuthal equal area||lambert_azimuthal_equal_area||Lambert_Azimuthal_Equal_Area||laea||9820|| ||
     33|| || ||longitude_of_projection_origin||longitude_of_center||lon_0|| || ||
     34|| || ||latitude_of_projection_origin||latitude_of_center||lat_0|| || ||
     35|| ||
     36||'''LCC-1SP'''||Lambert conformal||lambert_conformal_conic||Lambert_Conformal_Conic_1SP||lcc||9801||(3) [http://www.remotesensing.org/geotiff/proj_list/lambert_conic_conformal_1sp.html link]||
     37|| || ||standard_parallel||standard_parallel_1||lat_1|| || ||
     38|| || ||longitude_of_central_meridian||central_meridian||lon_0|| || ||
     39|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| || ||
     40|| || ||N/A||scale_factor||k_0|| ||always 1 (3)||
     41|| ||
     42||'''LCC-2SP'''||Lambert conformal||lambert_conformal_conic||Lambert_Conformal_Conic_2SP||lcc||9802||(3) [http://www.remotesensing.org/geotiff/proj_list/lambert_conic_conformal_2sp.html link]||
     43|| || ||standard_parallel![1]||standard_parallel_1||lat_1|| || ||
     44|| || ||standard_parallel![2]||standard_parallel_2||lat_2|| || ||
     45|| || ||longitude_of_central_meridian||central_meridian||lon_0|| || ||
     46|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| || ||
     47|| ||
     48||'''CEA'''||Lambert cylindrical equal area||lambert_cylindrical_equal_area||Cylindrical_Equal_Area||cea||9834/9835||(3)||
     49|| || ||longitude_of_central_meridian||central_meridian||lon_0|| || ||
     50|| || ||standard_parallel![1]||standard_parallel_1||lat_ts|| || ||
     51|| ||
     52||'''M-1SP'''||Mercator (1SP)||mercator||Mercator_1SP||merc||9804||(3)||
     53|| || ||longitude_of_projection_origin||central_meridian||lon_0|| || ||
     54|| || ||scale_factor_at_projection_origin||scale_factor||k_0|| || ||
     55|| ||
     56||'''M-2SP'''||Mercator (2SP)||mercator||Mercator_2SP||merc||9805||(3)||
     57|| || ||longitude_of_projection_origin||central_meridian||lon_0|| || ||
     58|| || ||standard_parallel![1]||standard_parallel_1||lat_1|| || ||
     59|| ||
     60||'''Ortho'''||Orthographic||orthographic||Orthographic||ortho||9840|| ||
     61|| || ||longitude_of_projection_origin||central_meridian||lon_0|| || ||
     62|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| || ||
     63|| ||
     64||'''PS'''||Polar stereographic||polar_stereographic||Polar_Stereographic||stere||9010/9829||(3)||
     65|| || ||standard_parallel![1]||latitude_of_origin||lat_0|| || ||
     66|| || ||straight_vertical_longitude_from_pole  ||central_meridian||lon_0|| || ||
     67|| ||
     68||'''St'''||Stereographic||stereographic||Stereographic||stere||9809|| ||
     69|| || ||longitude_of_projection_origin||central_meridian||lon_0|| || ||
     70|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| || ||
     71|| || ||scale_factor_at_projection_origin||scale_factor||k_0|| || ||
     72|| ||
     73||'''TM'''||Transverse Mercator||transverse_mercator||Transverse_Mercator||tm/utm||9807||(3)||
     74|| || ||scale_factor_at_central_meridian||scale_factor||k_0|| || ||
     75|| || ||longitude_of_central_meridian||central_meridian||lon_0|| || ||
     76|| || ||latitude_of_projection_origin||latitude_of_origin||lat_0|| || ||
     77
     78'''Notes:'''
     79
     80(1) Multiple CF/WKT translations, see projection-specific translations.
     81(2) Parameter used in every projection.
     82(3) See projection-specific notes below.
     83
     84=== Projection-specific notes ===
     85
     86EPSG codes below correspond to "EPSG dataset coordinate operation method" codes.
     87
     88==== Lambert conformal 1SP / 2SP ====
     89
     90The 1SP variant corresponds to EPSG code 9801 - Lambert Conic Conformal (1SP), with CF latitude_of_projection_origin=standard_parallel and WKT scale_factor=1. A scale factor less than 1 means that there are 2 standard parallels (see http://www.remotesensing.org/geotiff/proj_list/lambert_conic_conformal_1sp.html), but it cannot be translated to the CF 1SP variant, therefore the 2SP variant should be used instead. The 2SP variant corresponds to EPSG code 9802 - Lambert Conic Conformal (2SP).
     91
     92==== Lambert cylindrical equal area ====
     93
     94The scale_factor_at_projection_origin variant is not recommended as it does not translate to and from WKT/PROJ.4. Snyder formulas 10-2b and 10-2 can be used to relate scale_factor_at_projection_origin, standard_parallel1 and latitude_of_projection_origin but the latter is not part of this projection's parameters. It has been proposed to deprecate or remove this variant from the CF spec (see CF trac ticket #75).
     95
     96==== Mercator 1SP / 2SP ====
     97The scale_factor_at_projection_origin variant corresponds to EPSG code 9804 - Mercator (1SP) or Mercator (variant A), and the standard_parallel variant corresponds to EPSG code 9805 - Mercator (2SP) or Mercator (variant B).
     98
     99==== Polar stereographic ====
     100
     101The standard_parallel variant corresponds to EPSG code 9829 - Polar Stereographic (Variant B), while the scale_factor_at_projection_origin variant corresponds to EPSG code 9810 - Polar Stereographic (Variant A). As WKT/PROJ.4 require the standard parallel, [Snyder] formula 21-7 can be used to compute it from scale_factor_at_projection_origin if that variant is used.
     102
     103==== Transverse Mercator ====
     104
     105Transverse Mercator can be translated to PROJ.4 using either +proj=merc (Transverse Mercator) or +proj=utm (Universal Transverse Mercator) by computing zone number from longitude_of_central_meridian.
     106For example, a TM projection with longitude_of_central_meridian=-117 would have the corresponding PROJ.4 string: '+proj=utm +zone=11 +datum=NAD27 +units=m +no_defs '
     107
     108
    1109== Status of NetCDF CF-1.5 projection handling capability in work-in-progress NetCDF driver upgrade ==
    2110