PostGIS 1.5.8 Manual - Fedora Project Packages GIT repositories

PostGIS 1.5.8 Manual263 / 310DescriptionReturns Z minima of a bounding box 2d or 3d or a geometry.NoteAlthough this function is only defined for box3d, it will work for box2d and geometry because of the auto-casting behaviordefined for geometries and box2d. However you can not feed it a geometry or box2d text represenation, since that willnot auto-cast.This function supports 3d and will not drop the z-index.This method supports Circular Strings and CurvesExamplesSELECT ST_ZMin(’BOX3D(1 2 3, 4 5 6)’);st_zmin-------3SELECT ST_ZMin(ST_GeomFromEWKT(’LINESTRING(1 3 4, 5 6 7)’));st_zmin-------4SELECT ST_ZMin(’BOX3D(-3 2 1, 3 4 1)’ );st_zmin-------1--Observe THIS DOES NOT WORK because it will try to autocast the string representation to a ←↪BOX3DSELECT ST_ZMin(’LINESTRING(1 3 4, 5 6 7)’);--ERROR:BOX3D parser - doesnt start with BOX3D(SELECT ST_ZMin(ST_GeomFromEWKT(’CIRCULARSTRING(220268 150415 1,220227 150505 2,220227150406 3)’));st_zmin--------1←↪See AlsoST_GeomFromEWKT, ST_GeomFromText, ST_XMin, ST_XMax, ST_YMax, ST_YMin, ST_ZMax7.13 Exceptional FunctionsThese functions are rarely used functions that should only be used if your data is corrupted in someway. They are used fortroubleshooting corruption and also fixing things that should under normal circumstances, never happen.7.13.1 PostGIS_AddBBoxPostGIS_AddBBox — Add bounding box to the geometry.