[postgis-tickets] [PostGIS] #3487: wrong proj4text for epsg 31467

[PostGIS]

#3487: wrong proj4text for epsg 31467
-----------------------+---------------------------
  Reporter:  klemensp  |      Owner:  pramsey
      Type:  defect    |     Status:  closed
  Priority:  critical  |  Milestone:  PostGIS 2.2.2
 Component:  postgis   |    Version:  2.2.x
Resolution:  invalid   |   Keywords:  proj4text
-----------------------+---------------------------
Changes (by pramsey):

 * status:  new => closed
 * resolution:   => invalid


Comment:

 In spatial_ref_sys, the definition is
 {{{
 +proj=tmerc +lat_0=0 +lon_0=9 +k=1 +x_0=3500000 +y_0=0 +datum=potsdam
 +units=m +no_defs
 }}}
 The "datum" parameter embeds an implicit ellipse, whereas the epsg.io
 representation uses an explicit ellipse. Here's the code from proj.4
 defining the "potsdam" datum
 {{{
 src/pj_datums.c:
 "potsdam",  "towgs84=598.1,73.7,418.2,0.202,0.045,-2.455,6.7",  "bessel",
 "Potsdam Rauenberg 1950 DHDN",
 }}}
 This looks the same as what epsg.io is using. Having an explicit datum
 allows proj.4 to apply datum shift grids, where they exist, so this
 representation is preferable.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3487#comment:1>
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