PROJ/docs/source/operations/projections/tmerc.rst, branch 7.2

Fix typos spotted by scripts/fix_typos.sh

2020-10-25T15:18:58+00:00

Minor fixes to tmerc documentation

2020-10-23T19:32:35+00:00

merc.rst: revert to ln instead of log.

2020-10-22T17:53:45+00:00

Also define merc (resp. tmerc) as the conformal projection in which the
equator (resp. a chosen meridan} projects to a straight line at constant
scale.

Document the default poder_engsager algorithm for tmerc. (#2379)

2020-10-18T21:36:24+00:00

* Document the default poder_engsager algorithm for tmerc.

* Give exact expression for phi' in terms of phi

* Aadd another datapoint on range of applicability + explanation for
complex numbers.

* Update tmerc figure with one reflecting poder/engsager algo.

Courtesy of @hobu.

Co-authored-by: Charles Karney

Plot building Github Action (#2377)

2020-10-14T19:40:42+00:00

* implement conda package building

* paths

* need libtool

* PLATFORM check

* point to my PROJ feedstock for now

* point to PROJ repos

* plot building and artifact upload

* syntax

* add proj conda package for plotting

* retab

* no doxygen

* syntax

* update docs Makefile

* doc building

* needs

* consolidate doc/plots

* plot updates

* put updated plot output into docs

* register spelling module

* use v2 download-artifact

* artifact upload

tmerc/utm: add a +algo=auto/evenden_snyder/poder_engsager parameter

2020-04-14T23:07:18+00:00

The default remains +alg=poder_engsager.
This default value can be changed in proj.ini

+algo=auto will use Evenden Synder implementation if the error in
doing so remains below 0.1 mm on Earth-sized ellipsoid

Doc: use 'ellipsoidal' to refer to the ellipsoidal formulation (to be opposed to the spherical one)

2020-03-11T08:22:32+00:00

Instead of 'elliptical'.
Was suggested by @cffk in https://github.com/OSGeo/PROJ/pull/2030#issuecomment-596132341

An elliptical projection is a projection whose global shape fits inside an
ellipsoid, like Mollweide. At least according to
https://www.merriam-webster.com/dictionary/elliptical%20projection
and
https://en.wikipedia.org/wiki/Mollweide_projection

Remove occurences of deprecated PROJ.4 syntax

2020-03-04T23:18:01+00:00

+no_defs and +datum has no effect on the behaviour of proj, so can be
left out in these examples in the docs. +no_defs in rare occasions would
have had an effect in older PROJ versions but not from PROJ 6 and
onwards. +datum has ever only been honoured by cs2cs and pj_transform().

Fixes #2017

Some improvements to the docs for tmerc and omerc (#1281)

2019-02-24T13:21:26+00:00

Make tmerc an alias for etmerc. (#1234)

2019-02-11T22:58:16+00:00

* Make tmerc an alias for etmerc

This switches the algorithm used in tmerc to the Poder/Engsager
tmerc algorithm. The original tmerc algorithm of Evenden/Snyder
origin can still be accessed by adding the +approx flag when
initializing a tmerc projection. The +approx flag can also
be used when initializing UTM projections, in which case the
Evenden/Snyder algorithm is used as well.

If a tmerc projection is instantiated on a spherical earth
the Evenden/Snyder algorithm is used as well since the
Poder/Engsager algorithm is only defined on the ellipsoid.

+proj=etmerc can still be instantiated for backwards compatibility
reasons.

Co-authored-by: Kristian Evers 
Co-authored-by: Even Rouault