tribin error with 'remove accumulation bins with no data'

[G-kodes]

I am attempting to plot some data using matplotlib sub-figures (About 64 graphs total), and also plot a tri-bin shading using the log scaling and a gridsize of 4. All of my graphs work except one. I keep getting an error: IndexError: boolean index did not match indexed array along axis 0; size of axis is 16 but size of corresponding boolean axis is 17

When I trace the error, it is comming from this line of code:

mpltern/mpltern/ternary/_axes.py

Line 718 in d2cc1be

offsets = offsets[good_idxs, :]

In this snippet, the good_idxs boolean mask used to filter/keep the correct indices has one more entry than it should, causing a mismatch. In my use-case, I am able to trace the extra index item back to this line:

mpltern/mpltern/ternary/_axes.py

Line 693 in d2cc1be

indices = tribin_helpers.ternary_to_serial(gridsize, it, il, ir) + 1

When I lookup the function however, I cant seem to make heads or tails of how the ternary -> serial conversion works under the hood (Spesifically the i0, i and shift parameters). This error seems like an edge-case that has something to do with assigning tri-bin polygon indices to each data-point, and appears to be unique to this dataset. Could you help me understand this chunk of code so I could maybe try and diagnose the issue further?

mpltern/mpltern/tribin_helpers.py

Lines 34 to 82 in d2cc1be

	def ternary_to_serial(gridsize: int, it: int, il: int, ir: int) -> int:
	"""Convert serial index of triangles from ternary indices.
	Parameters
	----------
	gridsize : int
	Grid size.
	it : int
	Index for the t axis.
	il : int
	Index for the l axis.
	ir : int
	Index for the r axis.
	Returns
	-------
	i : int
	Serial index of triangles from ``0`` to ``gridsize ** 2 - 1``.
	If (``it``, ``il``, ``ir``) is out of the triangle with the grid size,
	``i == -1``.
	Upward triangles come first, followed by downward triangles.
	Examples
	--------
	The following gives the correspondence between the ternary and the serial
	indices when ``g == 3``.
	+------------------+-------+
	| ``(it, il, ir)`` | ``i`` |
	+==================+=======+
	| ``(2, 0, 0)`` | ``0`` |
	| ``(1, 1, 0)`` | ``1`` |
	| ``(1, 0, 1)`` | ``2`` |
	| ``(0, 2, 0)`` | ``3`` |
	| ``(0, 1, 1)`` | ``4`` |
	| ``(0, 0, 2)`` | ``5`` |
	| ``(1, 0, 0)`` | ``6`` |
	| ``(0, 1, 0)`` | ``7`` |
	| ``(0, 0, 1)`` | ``8`` |
	+------------------+-------+
	"""
	tmpt = (0 <= it) & (it <= gridsize)
	tmpl = (0 <= il) & (il <= gridsize)
	tmpr = (0 <= ir) & (ir <= gridsize)
	is_inside = tmpt & tmpl & tmpr
	i0 = (gridsize - it - 1) * (gridsize - it) // 2 + ir
	shift = gridsize * (gridsize + 1) // 2
	i1 = (gridsize - it - 2) * (gridsize - it - 1) // 2 + ir
	i = np.where(it + il + ir + 1 == gridsize, i0, i1 + shift)
	return np.where(is_inside, i, -1)

[G-kodes]

I ended up getting around this by changing my binsize to 5 and changing my gridlines to match via MultipleLocator. Now, they all render nicely.