Instead of being memoized all at once before display, functions values
are now stored at evaluation time. Fixed some quirks with caching
preparation.
Change-Id: I5d212c271c8c41a6dc9074a15c720f0bccf8ac40
The caches used for function values memoization are now stored in
ContinuousFunctionStore : there are now only a fixed number, instead of
one per function. This effectively enables caching only for the first
few functions on screen, while reducing the memory usage.
Change-Id: I2ade091717f73a14a756fe527c773db8e8627be7
ContinuousFunction now has an attribute of type ContinuousFunctionCache,
implementing methods to store and retrieve 320 float values, in order to
speed up function display in Graph.
Change-Id: I6f7ccdf3ae3c6dd8b08b93d786c8d0be7aa4dee8
