echolite/ses3d — pull request #1 by krischer (2014-08-06 14:02:56+00:00)
Title: Optional twelve component output

This pull requests adds support to optionally also output the rotation rates and strain rates at the receivers. It has to be chosen at compile time to be compatible with the current architecture of SES3D. Setting the `SAVE_TWELVE_COMPONENTS` macro will result in twelve component output. The compile script has been adjusted to show that possibility. The advantage of that approach is that it does not affect SES3D at all if the macro is not defined.

For a single receiver it will then produce the following files:

```
REC_NAME.x
REC_NAME.y
REC_NAME.z
REC_NAME.rot_x
REC_NAME.rot_y
REC_NAME.rot_z
REC_NAME.strain_xx
REC_NAME.strain_yy
REC_NAME.strain_zz
REC_NAME.strain_xy
REC_NAME.strain_xz
REC_NAME.strain_yz
```

We tested it against finite difference approximations of the rotation and strain components and it appears to work quite well. What we cannot really figure out is the cause of the noise on some strain and rotation components which is not present on the translational components. The following shows an example of the rotation around the y axis.

![index](https://cloud.githubusercontent.com/assets/800487/3827816/8b7752ea-1d71-11e4-804f-996ee3daeed2.png)

It is not present on the translational components and might just be an artifact of the small amplitude of the rotation rates but we are not sure. So maybe not yet ready to merge?

Also the manual should be updated. It might be useful to also put in on Github, maybe a separate repo but could also be the same so keeping it up to date is easier.