How to determine local coordinates of QUAD in SofimshA?

SOFiSTiK
1

According to official example: sofimsha.dat\english\3d_modeling\elastic_interface_02.dat
elastic_interface_02.dat (1.8 KB)

GRP 2 REF 12
QUAD PROP MNO 2 T 0
EXTR EDGE 1 PATH DIR  0  0  5 DIV 5

GRP 3 REF 13
QUAD PROP MNO 3 T 0
EXTR EDGE 2 PATH DIR  0  0  5 DIV 5
  1. Why local y axis of GRP 2 is downwards, while that of GRP 3 is upwards
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    image1742×1457 358 KB
  2. How to change direction of local Y axis in GRP 2 to upward, while keep the original local X direction?