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--- doc:user:geometry:user:points [2013/07/12 14:01] – [Définition] joris
+++ doc:user:geometry:user:points [2015/01/07 17:22] – boman
@@ Line 1: / Line 1: @@
+====== Points ======
+===== Definition =====
+Geometrical ''Points'' (e.g. vertices) are created thanks to an object called ''PointSet'' of the ''Geometry'' using the member function ''define()''. Once created, they are stored in the ''PointSet''.
+''Points'' are the geometrical entities of the lowest level. They are used to define later [[Courbes]].
+  pt = pointset.define(number, x, y [, z])
+with
+| ''number''          | user number (unique among Points and $\ge 1$)  |
+| ''x'', ''y'', ''z'' | coordinates of this point ($z=0$ by default)   |
+===== Example =====
+Definition of the 4 vertices of a square of length $L=5$. The python variable $L$ is used here to parametrize the positions of the points.
+  L=5
+  pointset = geometry.getPointset()
+  p1 = pointset.define(1, 0, 0)
+  p2 = pointset.define(2, L, 0)
+  p3 = pointset.define(3, L, L)
+  p4 = pointset.define(4, 0, L)
+The following command prints the created points as a list:
+  print pointset
+which produces the following output:
+  PointSet        of size 4 (hash=off)
+      Point #1 nDB=[1] (pos in DB) p=[0 0 0]
+      Point #2 nDB=[2] (pos in DB) p=[5 0 0]
+      Point #3 nDB=[3] (pos in DB) p=[5 5 0]
+      Point #4 nDB=[4] (pos in DB) p=[0 5 0]
+===== Note  =====
+{{:doc:user:ico-advanced.png?40 |}}
+Temporary points can be used to define ''[[doc:user:geometry:user:axes]]'' or ''[[doc:user:geometry:user:triedres]]'':
+  pt = Point(1, x, y, z)
+Since this Point was not defined using ''pointset.define()'', it will not be found in the ''PointSet''.