🌐EnglishEnglishDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsTürkçeРусскийالعربيةفارسیहिन्दी한국어中文日本語EntityQ1790208· pop 20· linked from 345 articlescurvilinear coordinate systemcoordinate system whose directions vary in spaceConnectionscoordinate systemEntityreal numberEntityCategoriesCoordinate systemsMetric tensors