Edit count of the user (user_editcount) | null |
Name of the user account (user_name) | '2001:569:BDF5:9A00:3901:72BD:D345:9FEB' |
Age of the user account (user_age) | 0 |
Groups (including implicit) the user is in (user_groups) | [
0 => '*'
] |
Rights that the user has (user_rights) | [
0 => 'createaccount',
1 => 'read',
2 => 'edit',
3 => 'createtalk',
4 => 'writeapi',
5 => 'viewmywatchlist',
6 => 'editmywatchlist',
7 => 'viewmyprivateinfo',
8 => 'editmyprivateinfo',
9 => 'editmyoptions',
10 => 'abusefilter-log-detail',
11 => 'urlshortener-create-url',
12 => 'centralauth-merge',
13 => 'abusefilter-view',
14 => 'abusefilter-log',
15 => 'vipsscaler-test'
] |
Whether the user is editing from mobile app (user_app) | false |
Whether or not a user is editing through the mobile interface (user_mobile) | false |
Page ID (page_id) | 62355111 |
Page namespace (page_namespace) | 0 |
Page title without namespace (page_title) | 'Snyder equal-area projection' |
Full page title (page_prefixedtitle) | 'Snyder equal-area projection' |
Edit protection level of the page (page_restrictions_edit) | [] |
Last ten users to contribute to the page (page_recent_contributors) | [
0 => 'Apocheir',
1 => 'Yobot',
2 => 'Cyfal',
3 => 'Krauss',
4 => 'WereSpielChequers',
5 => 'Sagotreespirit',
6 => 'Postcard Cathy'
] |
Page age in seconds (page_age) | 94349519 |
Action (action) | 'edit' |
Edit summary/reason (summary) | 'Snyder Projections is most often used in the ISEA (Icosahedron) Discrete Global Grid System not on truncated icosahedron, although the first division of the ISAE3H DGGS appears as a 32 partitions of the globe it is not a truncated icosahedron. Also, removed "For non-exact approximations (to equal-area) it can be replaced by Gnomonic projection, as in H3 Uber" as describing an alternative - and there are others - is irrelevant to the topic. ' |
Old content model (old_content_model) | 'wikitext' |
New content model (new_content_model) | 'wikitext' |
Old page wikitext, before the edit (old_wikitext) | ''''Snyder equal-area projection''' is a [[polyhedral map projection]] used in the ''[[Geodesic grid|ISEA]] (Icosahedral Snyder Equal Area) [[discrete global grid]]s''. It is named for John P. Snyder, who developed the projection in the 1990s.<ref name="snyder92">
Snyder, J. P. (1992), “An Equal-Area Map Projection for Polyhedral Globes”, Cartographica, 29(1), 10-21. [http://doi.org/10.3138/27H7-8K88-4882-1752 urn:doi:10.3138/27H7-8K88-4882-1752].
</ref>
It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of [[truncated icosahedron]] with 32 same-area faces (20 hexagons and 12 pentagons).<ref name="projOrg1">
PROJ guide's "Icosahedral Snyder Equal Area", [https://proj.org/operations/projections/isea.html#icosahedral-snyder-equal-area proj.org/operations/projections/isea.html]
</ref><ref name="Carr97">
D. Carr ''et al.'' (1997), "[https://www.researchgate.net/publication/246557072_ISEA_discrete_global_grids ISEA discrete global grids]"; in "Statistical Computing and Statistical Graphics Newsletter" vol. 8.
</ref>
For non-exact approximations (to equal-area) it can be replaced by [[Gnomonic projection]], as in ''H3 Uber''.<ref>[https://github.com/uber/h3/blob/master/docs/core-library/overview.md github.com/uber/h3 Overview]</ref><ref>[https://github.com/uber/h3/issues/237 github.com/uber/h3/issues/237]</ref>
[[File:DualTiling-TriangHex-fig1.png|thumb|With the [[Dual graph|dual]] [[Euclidean tilings by convex regular polygons|tiling system]] is possible to transform the big triangular faces (gray) into small centered-hexagons (red), and ''vice versa''.]]
== Use in the ISEA model ==
As stated by Carr at al. article,<ref name="Carr97"/> page 32:
: ''The S in ISEA refers to John P. Snyder. He came out of retirement specifically to address projection problems with the original EMAP grid (see Snyder, 1992). He developed the equal area projection that underlies the gridding system.
:
: ''ISEA grids are simple in concept. Begin with a Snyder Equal Area projection to a regular icosahedron (...) inscribed in a sphere. In each of the 20 equilateral triangle faces of the icosahedron inscribe a hexagon by dividing each triangle edge into thirds (...). Then project the hexagon back onto the sphere using the Inverse Snyder Icosahedral equal area projection. This yields a coarse-resolution equal area grid called the resolution 1 grid. It consists of 20 hexagons on the surface of the sphere and 12 pentagons centered on the 12 vertices of the icosahedron.''
== References ==
{{Reflist}}
{{Map Projections}}
{{cartography-stub}}
[[Category:Equal-area projections]]' |
New page wikitext, after the edit (new_wikitext) | ''''Snyder equal-area projection''' is a [[polyhedral map projection]] used in the ''[[Geodesic grid|ISEA]] (Icosahedral Snyder Equal Area) [[discrete global grid]]s''. It is named for John P. Snyder, who developed the projection in the 1990s.<ref name="snyder92">
Snyder, J. P. (1992), “An Equal-Area Map Projection for Polyhedral Globes”, Cartographica, 29(1), 10-21. [http://doi.org/10.3138/27H7-8K88-4882-1752 urn:doi:10.3138/27H7-8K88-4882-1752].
</ref>
It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of an [[icosahedron]] which minimize the areal distortions.<ref name="projOrg1">
PROJ guide's "Icosahedral Snyder Equal Area", [https://proj.org/operations/projections/isea.html#icosahedral-snyder-equal-area proj.org/operations/projections/isea.html]
</ref><ref name="Carr97">
D. Carr ''et al.'' (1997), "[https://www.researchgate.net/publication/246557072_ISEA_discrete_global_grids ISEA discrete global grids]"; in "Statistical Computing and Statistical Graphics Newsletter" vol. 8.
</ref><ref>{{Cite journal |last=Sahr |first=Kevin |last2=White |first2=Denis |last3=Kimerling |first3=A. Jon |date=2003-01-01 |title=Geodesic Discrete Global Grid Systems |url=https://www.tandfonline.com/doi/citedby/10.1559/152304003100011090 |journal=Cartography and Geographic Information Science |volume=30 |issue=2 |pages=121–134 |doi=10.1559/152304003100011090 |issn=1523-0406}}</ref>
[[File:DualTiling-TriangHex-fig1.png|thumb|With the [[Dual graph|dual]] [[Euclidean tilings by convex regular polygons|tiling system]] is possible to transform the big triangular faces (gray) into small centered-hexagons (red), and ''vice versa''.]]
== Use in the ISEA model ==
As stated by Carr at al. article,<ref name="Carr97"/> page 32:
: ''The S in ISEA refers to John P. Snyder. He came out of retirement specifically to address projection problems with the original EMAP grid (see Snyder, 1992). He developed the equal area projection that underlies the gridding system.
:
: ''ISEA grids are simple in concept. Begin with a Snyder Equal Area projection to a regular icosahedron (...) inscribed in a sphere. In each of the 20 equilateral triangle faces of the icosahedron inscribe a hexagon by dividing each triangle edge into thirds (...). Then project the hexagon back onto the sphere using the Inverse Snyder Icosahedral equal area projection. This yields a coarse-resolution equal area grid called the resolution 1 grid. It consists of 20 hexagons on the surface of the sphere and 12 pentagons centered on the 12 vertices of the icosahedron.''
== References ==
{{Reflist}}
{{Map Projections}}
{{cartography-stub}}
[[Category:Equal-area projections]]' |
Unified diff of changes made by edit (edit_diff) | '@@ -3,11 +3,9 @@
</ref>
-It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of [[truncated icosahedron]] with 32 same-area faces (20 hexagons and 12 pentagons).<ref name="projOrg1">
+It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of an [[icosahedron]] which minimize the areal distortions.<ref name="projOrg1">
PROJ guide's "Icosahedral Snyder Equal Area", [https://proj.org/operations/projections/isea.html#icosahedral-snyder-equal-area proj.org/operations/projections/isea.html]
</ref><ref name="Carr97">
D. Carr ''et al.'' (1997), "[https://www.researchgate.net/publication/246557072_ISEA_discrete_global_grids ISEA discrete global grids]"; in "Statistical Computing and Statistical Graphics Newsletter" vol. 8.
-</ref>
-
-For non-exact approximations (to equal-area) it can be replaced by [[Gnomonic projection]], as in ''H3 Uber''.<ref>[https://github.com/uber/h3/blob/master/docs/core-library/overview.md github.com/uber/h3 Overview]</ref><ref>[https://github.com/uber/h3/issues/237 github.com/uber/h3/issues/237]</ref>
+</ref><ref>{{Cite journal |last=Sahr |first=Kevin |last2=White |first2=Denis |last3=Kimerling |first3=A. Jon |date=2003-01-01 |title=Geodesic Discrete Global Grid Systems |url=https://www.tandfonline.com/doi/citedby/10.1559/152304003100011090 |journal=Cartography and Geographic Information Science |volume=30 |issue=2 |pages=121–134 |doi=10.1559/152304003100011090 |issn=1523-0406}}</ref>
[[File:DualTiling-TriangHex-fig1.png|thumb|With the [[Dual graph|dual]] [[Euclidean tilings by convex regular polygons|tiling system]] is possible to transform the big triangular faces (gray) into small centered-hexagons (red), and ''vice versa''.]]
' |
New page size (new_size) | 2755 |
Old page size (old_size) | 2696 |
Size change in edit (edit_delta) | 59 |
Lines added in edit (added_lines) | [
0 => 'It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of an [[icosahedron]] which minimize the areal distortions.<ref name="projOrg1">',
1 => '</ref><ref>{{Cite journal |last=Sahr |first=Kevin |last2=White |first2=Denis |last3=Kimerling |first3=A. Jon |date=2003-01-01 |title=Geodesic Discrete Global Grid Systems |url=https://www.tandfonline.com/doi/citedby/10.1559/152304003100011090 |journal=Cartography and Geographic Information Science |volume=30 |issue=2 |pages=121–134 |doi=10.1559/152304003100011090 |issn=1523-0406}}</ref>'
] |
Lines removed in edit (removed_lines) | [
0 => 'It is a modified [[Lambert azimuthal equal-area projection]], most often applied to a [[polyhedral globe]] consisting of [[truncated icosahedron]] with 32 same-area faces (20 hexagons and 12 pentagons).<ref name="projOrg1">',
1 => '</ref>',
2 => '',
3 => 'For non-exact approximations (to equal-area) it can be replaced by [[Gnomonic projection]], as in ''H3 Uber''.<ref>[https://github.com/uber/h3/blob/master/docs/core-library/overview.md github.com/uber/h3 Overview]</ref><ref>[https://github.com/uber/h3/issues/237 github.com/uber/h3/issues/237]</ref>'
] |
All external links added in the edit (added_links) | [
0 => 'https://www.tandfonline.com/doi/citedby/10.1559/152304003100011090',
1 => '//doi.org/10.1559%2F152304003100011090',
2 => '//www.worldcat.org/issn/1523-0406'
] |
All external links removed in the edit (removed_links) | [
0 => 'https://github.com/uber/h3/blob/master/docs/core-library/overview.md',
1 => 'https://github.com/uber/h3/issues/237'
] |
All external links in the new text (all_links) | [
0 => 'http://doi.org/10.3138/27H7-8K88-4882-1752',
1 => 'https://proj.org/operations/projections/isea.html#icosahedral-snyder-equal-area',
2 => 'https://www.researchgate.net/publication/246557072_ISEA_discrete_global_grids',
3 => 'https://www.tandfonline.com/doi/citedby/10.1559/152304003100011090',
4 => '//doi.org/10.1559%2F152304003100011090',
5 => '//www.worldcat.org/issn/1523-0406'
] |
Links in the page, before the edit (old_links) | [
0 => 'http://doi.org/10.3138/27H7-8K88-4882-1752',
1 => 'https://github.com/uber/h3/blob/master/docs/core-library/overview.md',
2 => 'https://github.com/uber/h3/issues/237',
3 => 'https://proj.org/operations/projections/isea.html#icosahedral-snyder-equal-area',
4 => 'https://www.researchgate.net/publication/246557072_ISEA_discrete_global_grids'
] |
Whether or not the change was made through a Tor exit node (tor_exit_node) | false |
Unix timestamp of change (timestamp) | '1668190325' |