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make numpy style docstring of arrayToQPath

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The function had many comments/explanations, decided to convert to
numpy docstring style, which is the direction pyqtgraph is going in
as it stands
This commit is contained in:
Ogi Moore 2021-06-03 21:53:36 -07:00
parent 649757eb31
commit 55e42aabfd
1 changed files with 48 additions and 15 deletions
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63
pyqtgraph/functions.py
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@ -1679,27 +1679,60 @@ def downsample(data, n, axis=0, xvals='subsample'):
def arrayToQPath(x, y, connect='all', finiteCheck=True):
"""Convert an array of x,y coordinates to QPainterPath as efficiently as
"""
Convert an array of x,y coordinates to QPainterPath as efficiently as
possible. The *connect* argument may be 'all', indicating that each point
should be connected to the next; 'pairs', indicating that each pair of
points should be connected, or an array of int32 values (0 or 1) indicating
connections.
Parameters
----------
x : (N,) ndarray
x-values to be plotted
y : (N,) ndarray
y-values to be plotted, must be same length as `x`
connect : {'all', 'pairs', 'finite', (N,) ndarray}, optional
Argument detailing how to connect the points in the path. `all` will
have sequential points being connected. `pairs` generates lines
between every other point. `finite` only connects points that are
finite. If an ndarray is passed, containing int32 values of 0 or 1,
only values with 1 will connect to the previous point. Def
finiteCheck : bool, default Ture
When false, the check for finite values will be skipped, which can
improve performance. If finite values are present in `x` or `y`,
an empty QPainterPath will be generated.
Returns
-------
QPainterPath
QPainterPath object to be drawn
Raises
------
ValueError
Raised when the connect argument has an invalid value placed within.
Notes
-----
A QPainterPath is generated through one of two ways. When the connect
parameter is 'all', a QPolygonF object is created, and
``QPainterPath.addPolygon()`` is called. For other connect parameters
a ``QDataStream`` object is created and the QDataStream >> QPainterPath
operator is used to pass the data. The memory format is as follows
numVerts(i4)
0(i4) x(f8) y(f8) <-- 0 means this vertex does not connect
1(i4) x(f8) y(f8) <-- 1 means this vertex connects to the previous vertex
...
cStart(i4) fillRule(i4)
see: https://github.com/qt/qtbase/blob/dev/src/gui/painting/qpainterpath.cpp
All values are big endian--pack using struct.pack('>d') or struct.pack('>i')
This binary format may change in future versions of Qt
"""
# Create all vertices in path. The method used below creates a binary format so that all
# vertices can be read in at once. This binary format may change in future versions of Qt,
# Speed this up using >> operator
# Format is:
# numVerts(i4)
# 0(i4) x(f8) y(f8) <-- 0 means this vertex does not connect
# 1(i4) x(f8) y(f8) <-- 1 means this vertex connects to the previous vertex
# ...
# cStart(i4) fillRule(i4)
#
# see: https://github.com/qt/qtbase/blob/dev/src/gui/painting/qpainterpath.cpp
# All values are big endian--pack using struct.pack('>d') or struct.pack('>i')
path = QtGui.QPainterPath()
n = x.shape[0]