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geosketch_data_analysis

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Geosketch Data Analysis

plunder database

table georegions, originally 1048 records from osmtilemill shapefiles

attributes featureclass and scalerank

scalerank

scale = the number of pixels in the radius of the globe, used for realtime map drawing

scalerank = a number from 1 to 6, indicating the relative magnitude of the feature

featureclass

featureclass count
alkaline lake 40
basin 9
canal 4
coast 36
continent 7
delta 12
depression 2
desert* 58
drangons-be-here 1
empire 427
foothills* 3
geoarea 44
gorge 3
island 295
island group 167
isthmus 4
lake 320
lake centerline 113
lowland 5
pen/cape 55
peninsula 11
plain* 30
plateau* 71
range/mtn* 222
reservoir* 52
river* 361
treasure* 67
tundra* 4
valley* 6
wetlands* 3

* classes used in the original plunder

water

loaded from Natural Earth Data, 50m set

  • oceans
  • seas
  • lakes
  • rivers

rivers

A. examine rivers 1:50m 460 rivers, scalerank 1 thru 6, 42 rows in our target geo

#all rivers combined, almost 1 MB psql -t -d voyc -U jhagstrand <rivers.sql >../json/rivers.js

lakes

select scalerank, count(*) from plunder.plunder
where featureclass = 'lake'
group by scalerank order by scalerank;

       0 |   220
       1 |    58
       2 |     2
       3 |     5
       4 |     2
       5 |     7
       6 |    26

select scalerank, count(*) from plunder.plunder
where featureclass = 'reservoir group by scalerank order by scalerank;

       0 |    25
       1 |     8
       2 |     1
       4 |     5
       5 |     4
       6 |     9

seas

A table on this page includes names of the major seas. https://en.wikipedia.org/wiki/List_of_political_and_geographic_borders

Caspian Sea is currently missing.

Maybe needed for labeling or hit testing.

Examples

  • Mediterranean
  • Bay of Bengal
  • Arabian Sea
  • Carribean

oceans

Natural Earth's Ocean file has only one polygon.

We don't currently have an oceans data. We just paint the background blue, and start drawing on top of it.

If we want to do labeling or hit testing by ocean name, then we will need a polygon for each named ocean.

3 oceans: Pacific, Atlantic, Indian
optional: Arctic, Southern
optional: North Pacific, South Pacific, North Atlantic, South Atlantic

arctic and southern oceans are each a circle, or just explicitly test for north of 80

Political data

pulled from database voyc, table fpd

  • empire - polygon
  • treasure - point
geosketch_data_analysis.1671240510.txt.gz ยท Last modified: 2022/12/16 20:28 by jhagstrand

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