remove legacy drive conventions and functions

[rythorpe]

I think this merits it's own issue. Quoting @cjayb,

OK, drives.py:drive_event_times is the remains of feeds.py, i.e., deprecated (used to be called feed_event_times). The test test_drives.py:test_external_drive_times is basically testing that the expected "default" drives are read from the params-file, and that the gid-assignments are 'correct' insofar as they reproduce default GUI output.

That can all go, though I suppose we should immediately open a follow-up PR to implement tests of drives.py:_drive_cell_event_times!

I'd also like to point out that I think this hack might be worth removing in this PR

hnn-core/hnn_core/network.py

Lines 589 to 595 in d6b08ff

	# this is needed to keep the drive GIDs identical to those in HNN,
	# e.g., 'evdist1': range(272, 542), even when no L5_basket cells
	# are targeted (event times lists are empty). The logic in
	# _connect_celltypes is hard-coded to use these implict gid ranges
	if self._legacy_mode:
	# XXX tests must match HNN GUI output
	target_populations = list(self.cell_types.keys())

The tricky part is here for cases when all weights are zero (at least is used to be a problem before this PR...):

hnn-core/hnn_core/network_builder.py

Lines 474 to 477 in d6b08ff

	pos_idx = src_gid - net.gid_ranges[_long_name(src_type)][0]
	# NB pos_dict for this drive must include ALL cell types!
	nc_dict['pos_src'] = net.pos_dict[
	_long_name(src_type)][pos_idx]

Originally posted by @cjayb in #383 (comment)

[rythorpe]

OK, drives.py:drive_event_times is the remains of feeds.py, i.e., deprecated (used to be called feed_event_times). The test test_drives.py:test_external_drive_times is basically testing that the expected "default" drives are read from the params-file, and that the gid-assignments are 'correct' insofar as they reproduce default GUI output.

That can all go, though I suppose we should immediately open a follow-up PR to implement tests of drives.py:_drive_cell_event_times!

I totally agree, let's get rid of drives.drive_event_times() in favor of building tests off of drives._drive_cell_event_times.

I'd also like to point out that I think this hack might be worth removing in this PR

hnn-core/hnn_core/network.py

Lines 589 to 595 in d6b08ff

	# this is needed to keep the drive GIDs identical to those in HNN,
	# e.g., 'evdist1': range(272, 542), even when no L5_basket cells
	# are targeted (event times lists are empty). The logic in
	# _connect_celltypes is hard-coded to use these implict gid ranges
	if self._legacy_mode:
	# XXX tests must match HNN GUI output
	target_populations = list(self.cell_types.keys())

[Updated as of this comment] I'm actually in favor of making

target_populations = list(self.cell_types.keys())

standard practice (not just legacy) because it ensures that artificial drive cells are created irrespective of the location of the drive or specific cell types within the network. This seems like good practice as it simplifies the logic for how/when an artificial cell gets created.

[cjayb]

Hmm, interesting! I think this makes a lot of sense after your work in #383 Either way, removes the need for the legacy-flag

[jasmainak]

@rythorpe does something remain unaddressed in this PR after #369 ?

[rythorpe]

Nope.

[rythorpe]

Any residual issue(s) were addressed in #431.