#247 indicex() method for GeometryType
Metadata
| Property | Value |
|---|---|
| Reported by | Carsten Gräser (graeser@math.fu-berlin.de) |
| Reported at | Jan 26, 2007 15:50 |
| Type | Feature Request |
| Version | Git (pre2.4) [autotools] |
| Operating System | Unspecified / All |
| Last edited by | Oliver Sander (oliver.sander@tu-dresden.de) |
| Last edited at | Oct 20, 2008 19:57 |
| Closed by | Oliver Sander (oliver.sander@tu-dresden.de) |
| Closed at | Oct 20, 2008 19:57 |
| Closed in version | Unknown |
| Resolution | Won't implement |
| Comment | No reaction -- no numbers showing that this is really important. Closing as 'wont't implement'. |
Description
I suggest to add an index to each GeometryType for the following reasons:
1)Since indices are only consecutive within one GeometryType, one can not avoid an GeometryType->something map if you want to associate Information to an entity. This could be 'map<GeometryType,vector>' or 'map<GeometryType,someIndexOffset>'. But even if the map is small this is slower then a corresponding 'vector' or 'vector' approach. Having an index one could use this faster approach.
2)For the current GeometryTypes this could be computed on the fly by unsigned int index() const {if (dim_<2) return dim_; return 4*dim_ + basicType_ - 6;}
3)This improvement might be small in general, but if you do a lot of index/subindex operations and no or just a few numerical computations it is significant, especially in combination with #246 (closed).