[Feature] Improve memory usage of TPWALikelihood [sf#20]

[legordian]

Reported by sebastianuhl on 2013-11-05 03:22 UTC
TPWALikelihood stores the decay amplitudes in the array decayAmps. decayAmps has the size (#events)(2)(maximum of the number of waves vs. reflectivity). The factor two is due to the two possible reflectivity states. Given that the number of waves in the two reflectivities is typically very different, or waves with negative reflectivity are even completely omitted, this seems to be quite wasteful. _decayAmps should actually occupy the greatest part of the memory allocated during the mass-independent fit, which means that for the typical 3pi analysis around 40% of the allocated memory are not used at all. Let me also remind you, that the model-independent extraction of the (pipi)S wave cannot be done on 32 bit systems as the required memory exceeds the addressable range, a reduction of the allocated memory would be helpful.