lqg2stan returns wrong (inverted) values
#### Reported by **Vincent COUVERT** (@vincent.couvert)
[testErr2Scilab.sce (2.26 KB, text/x-csrc)](/uploads/f0ccbcab280d03f828faeaa9622797ec/testErr2Scilab.sce)
```
Script to reproduce the bug
BUG DESCRIPTION:
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lqg2stan returns wrong (inverted) values
ERROR LOG:
----------
No error but the result is wrong.
HOW TO REPRODUCE THE BUG:
-------------------------
See files attached
OTHER INFORMATION:
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P22=-P22; must be removed at line 27 of lqg2stan.sci
```
issue