CSV (Comma-Separated Values)
Open BetaCSV með WKT-rúmfræði er algilt textasnið fyrir gagnaskipti á landupplýsingum. Opnast í hvaða töflureikni sem er, flyst auðveldlega inn í gagnagrunna og er notað í gagnavinnsluskriftum.
Helstu eiginleikar
Um CSV-sniðið
CSV is a simple table: a row per object, columns separated by commas. Geography is put into it in two ways, and we use both at once: the full geometry of an object is written as text in WKT format, and next to it come the latitude and longitude of a representative point — for a line and a polygon that is a point on the object itself, not a nominal center outside it.
The format is chosen when the map is needed as data rather than as a picture: to count objects in a table, to merge with an export from your own system, to load into a database, to hand to a colleague without a GIS, to run through a script. CSV is read by literally everything — from Excel to pandas.
The output is a single file in UTF-8 encoding. One layer gives an ordinary table; if several layers are selected, they are gathered into one file, and the first column _layer shows where the row came from — it makes splitting the data back apart easy. OSM attributes go as separate columns, and the coordinates are in WGS84 rounded to seven decimal places, which is about a centimeter.
Hvaða forrit opnar CSV-skrár
Eftirfarandi forrit geta opnað, breytt og unnið með CSV (Comma-Separated Values) (.csv) skrár sem fluttar eru út úr OSM2CDR:
Format specifications
- Open standard
- 2D only
- Lossless (no quality loss)
- Stores feature attributes
- Output: 1 file
- RFC 4180 CSV with WKT geometry column or lat/lon pairs. UTF-8 encoded. Opens in Excel, LibreOffice, pandas, QGIS.
Hverjir nota CSV-kort
Hvernig á að flytja út CSV
Hvernig á að opna eftir útflutning
- Excel — do not open the file with a double click, otherwise non-Latin text turns into gibberish: Data → Get Data → From Text/CSV, encoding UTF-8, comma as the separator.
- QGIS — Layer → Add Layer → Add Delimited Text Layer; choose the WKT column as the geometry, coordinate system EPSG:4326.
- Python — pandas.read_csv for the table, and for the geometry shapely.wkt.loads on the WKT column, or geopandas straight away if you need spatial analysis.
- PostGIS — load the table with the COPY command and turn the text into geometry through ST_GeomFromText with SRID 4326.
- Google Sheets and My Maps — accept the latitude and longitude columns directly, if a point representation of the objects is enough.
Vinsæl kort í CSV
Fáðu kortaútflutning í CSV (Comma-Separated Values)
Sæktu fagleg CSV-kort úr OpenStreetMap. Tafarlaus kortagerð, hvaða svæði sem er.
Algengar spurningar
Berðu saman við önnur snið
Convert to CSV and back
CSV guides and tutorials
Tengd snið
Oft flutt út saman
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