def array2d_to_qpolygonf(xdata, ydata):
"""
Utility function to convert two 1D-NumPy arrays representing curve data
(X-axis, Y-axis data) into a single polyline (QtGui.PolygonF object).
This feature is compatible with PyQt4, PyQt5 and PySide2 (requires QtPy).
License/copyright: MIT License © Pierre Raybaut 2020.
:param numpy.ndarray xdata: 1D-NumPy array (numpy.float64)
:param numpy.ndarray ydata: 1D-NumPy array (numpy.float64)
:return: Polyline
:rtype: QtGui.QPolygonF
"""
dtype = np.float
if not (xdata.size == ydata.size == xdata.shape[0] == ydata.shape[0]
and xdata.dtype == ydata.dtype == dtype):
raise ValueError(
"Arguments must be 1D, float64 NumPy arrays with same size")
size = xdata.size
polyline = QPolygonF(size)
if PYSIDE2: # PySide2 (obviously...)
address = shiboken2.getCppPointer(polyline.data())[0]
buffer = (ctypes.c_double * 2 * size).from_address(address)
else: # PyQt4, PyQt5
buffer = polyline.data()
buffer.setsize(2 * size * np.finfo(dtype).dtype.itemsize)
memory = np.frombuffer(buffer, dtype)
memory[:(size - 1) * 2 + 1:2] = xdata
memory[1:(size - 1) * 2 + 2:2] = ydata
return polyline
def array2d_to_qpolygonf(xdata, ydata):
"""
Utility function to convert two 1D-NumPy arrays representing curve data
(X-axis, Y-axis data) into a single polyline (QtGui.PolygonF object).
This feature is compatible with PyQt4, PyQt5 and PySide2 (requires QtPy).
License/copyright: MIT License © Pierre Raybaut 2020-2021.
:param numpy.ndarray xdata: 1D-NumPy array
:param numpy.ndarray ydata: 1D-NumPy array
:return: Polyline
:rtype: QtGui.QPolygonF
"""
if not (xdata.size == ydata.size == xdata.shape[0] == ydata.shape[0]):
raise ValueError("Arguments must be 1D NumPy arrays with same size")
size = xdata.size
if QT_API.startswith("pyside"): # PySide (obviously...)
if QT_API == "pyside2":
polyline = QPolygonF(size)
else:
polyline = QPolygonF()
polyline.resize(size)
address = shiboken.getCppPointer(polyline.data())[0]
buffer = (ctypes.c_double * 2 * size).from_address(address)
else: # PyQt4, PyQt5
if QT_API == "pyqt6":
polyline = QPolygonF([QPointF(0, 0)] * size)
else:
polyline = QPolygonF(size)
buffer = polyline.data()
buffer.setsize(
16 * size) # 16 bytes per point: 8 bytes per X,Y value (float64)
memory = np.frombuffer(buffer, np.float64)
memory[:(size - 1) * 2 + 1:2] = np.array(xdata,
dtype=np.float64,
copy=False)
memory[1:(size - 1) * 2 + 2:2] = np.array(ydata,
dtype=np.float64,
copy=False)
return polyline
