GeoCSV: Unterschied zwischen den Versionen

Aus Geoinformation HSR
Wechseln zu: Navigation, Suche
K
K (→‎Example)
Zeile 55: Zeile 55:
  
 
=== Example ===
 
=== Example ===
 +
 +
<pre>
 +
id;name;amount;remarks;geom
 +
1;Adam;2.1;Mathe;point(10 20)
 +
2;Eva;2.2;Sport;point(30 40)
 +
3;"Jimmy;Muff";2.3;;point(50 60)
 +
</pre>
 +
 +
repräsentiert die folgende Tabelle:
 +
 +
{|class="wikitable"
 +
|-
 +
! id
 +
! name
 +
! amount
 +
! remarks
 +
! geom
 +
|-
 +
| 1
 +
| Adam
 +
| 2.1
 +
| Französisch
 +
| point(10 20)
 +
|-
 +
| 2
 +
| Eva
 +
| 2.2
 +
| "Jimmy;Muff"
 +
| point(30 40)
 +
|-
 +
| 2
 +
| Jim
 +
| 2.3
 +
|
 +
| point(50 60)
 +
|}

Version vom 1. Mai 2015, 01:35 Uhr

Specification of the tabular file format CSV (Comma Separated Values) with a geometry extension!

CSV file format specification

  • Encoding is UTF-8 by default.
  • First row contains attribute names separated by a => delimiter.
  • Following rows are contains values separated by a => delimiter.
  • Delimiter is semicolon (;) by default.
  • Strings are enclosed by parantheses, to allow delimiters inside (e.g. "string").
  • Data types (if supported from source or target system): See CSVT file format specification.

Notes:

  • End-of-lines are: CR, LF or CR/LF.
  • All rows have same number of attributes.
  • Line Breaks in (String) fields are disallowed.
  • Calculations are possible

GeoCSV file format specification

GeoCSV is based on CSV. The extension comes with two variants: Options easting/northing and Options WKT.

Option "easting/northing" (longitude/latitude, similar to x/y in mathematics):

  • Geometry Point type as two neighboring columns of type Float: one containing the easting coordinate, and one containing northing coordinate separated by the common delimiter.
  • Example for the two easting/northing columnts "8.8249;47.2274".
  • This option supports only Points.

Option WKT:

  • It' one single column of type String containing a constructor, like for example: "POINT (8.8249 47.2274)".
  • This option supports Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon.
  • WKT ("Well Known Text") is originally defined by the Open Geospatial Consortium (OGC) and described in their Simple Feature Access specification (also ISO SQL/MM). See e.g. http://en.wikipedia.org/wiki/Well-known_text

Common restrictions:

  • Coordinate system is WGS84 (EPSG:4326) by default.
  • There is only one geometry column allowed per sheet.
  • All geometry values within one table are in the same coordinate reference system (CRS).

CSVT file format specification

Field/column types, case insensitive (if supported from source or target system):

  • Integer
  • Real
  • String
  • Date ("YYYY-MM-DD"), Time ("HH:MM:SS+nn") and DateTime (YYYY-MM-DD HH:MM:SS+nn)
  • (lon/lat)
  • (WKT)

Notes:

  • The geometry types are a kind of subtype: easting and northing values are stored as float, option WKT is stored in one column of type String.
  • See also http://www.gdal.org/drv_csv.html section with .csvt extension.

Software

Example

id;name;amount;remarks;geom
1;Adam;2.1;Mathe;point(10 20)
2;Eva;2.2;Sport;point(30 40)
3;"Jimmy;Muff";2.3;;point(50 60)

repräsentiert die folgende Tabelle:

id name amount remarks geom
1 Adam 2.1 Französisch point(10 20)
2 Eva 2.2 "Jimmy;Muff" point(30 40)
2 Jim 2.3 point(50 60)
Von «https://giswiki.hsr.ch/index.php?title=GeoCSV&oldid=55026»