Table:
Advantages (+) and disadvantages (-) of LMV and VLM-ordered
Class cubes
# |
Position-Position-Velocity (LMV) |
Velocity-Position-Position (VLM) |
9 |
- |
need transposing the convolved data before writing to the file |
+ |
correctly ordered, convolved data can be written as is |
10 |
+ |
the cube can easily be extended by block of velocities, in particular
it may not fit in memory |
- |
the cube can not (reasonably) be extended on disk. If it fits in
memory, it can be written in a temporary output buffer, with more
memory cost. |
11 |
+ |
default ordering in Gildas, efficient for the imaging tools (one
image plane is contiguous in the file) |
- |
not the default in Gildas, many tools do not expect such order |
12 |
- |
need transposing for an efficient per spectrum analysis |
+ |
the order is correct for spectrum-oriented tools like Class or Cube. |