#181 P1 shape functions for pyramid are buggy
Metadata
| Property | Value |
|---|---|
| Reported by | Oliver Sander (oliver.sander@tu-dresden.de) |
| Reported at | Oct 9, 2006 08:32 |
| Type | Bug Report |
| Version | Git (pre2.4) [autotools] |
| Operating System | Unspecified / All |
| Last edited by | Oliver Sander (oliver.sander@tu-dresden.de) |
| Last edited at | Sep 23, 2008 17:37 |
| Closed by | Oliver Sander (oliver.sander@tu-dresden.de) |
| Closed at | Sep 23, 2008 17:37 |
| Closed in version | Unknown |
| Resolution | Not a bug |
| Comment | This is not a bug. The shape functions really are not differentiable everywhere. |
Description
The first-order shape functions 0-3 for the pyramid have buggy first derivatives, as witnessed by the unit test 'lagrangeshapefunctiontest':
Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 0 at position 0 0 1: derivative in direction 0 is 0, but -0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 0 at position 0 0 1: derivative in direction 1 is -1, but -0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 1 at position 0 0 1: derivative in direction 0 is 0, but 0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 1 at position 0 0 1: derivative in direction 1 is -0, but -0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 2 at position 0 0 1: derivative in direction 0 is 1, but 0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 2 at position 0 0 1: derivative in direction 1 is 0, but 0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 3 at position 0 0 1: derivative in direction 0 is -1, but -0.5 is expected. Bug in shape function of order 1 for pyramid. Shape function derivative does not agree with FD approximation Shape function 3 at position 0 0 1: derivative in direction 1 is 1, but 0.5 is expected.