ASCEE/pyqtgraph
5
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

only use np.searchsorted quicker method fails

Browse Source
This commit is contained in:
Sam Schott 2019-06-24 13:53:00 +01:00
parent 365c13fedc
commit f23889d594
1 changed files with 19 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
pyqtgraph/graphicsItems/PlotDataItem.py
View File

@ -543,13 +543,25 @@ class PlotDataItem(GraphicsObject):
# this option presumes that x-values are in increasing order
range = self.viewRect()
if range is not None and len(x) > 1:
# clip to visible region extended by downsampling value
idx = np.searchsorted(x, [range.left(), range.right()])
idx = idx + np.array([-2*ds, 2*ds])
idx = np.clip(idx, a_min=0, a_max=len(x))
x = x[idx[0]:idx[1]]
y = y[idx[0]:idx[1]]
# clip to visible region extended by downsampling value, assuming
# uniform spacing of x-values, has O(1) performance
dx = float(x[-1]-x[0]) / (len(x)-1)
x0 = np.clip(int((range.left()-x[0])/dx) - 1*ds, 0, len(x)-1)
x1 = np.clip(int((range.right()-x[0])/dx) + 2*ds, 0, len(x)-1)
# if data has been clipped too strongly (in case of non-uniform
# spacing of x-values), refine the clipping region as required
# worst case performance: O(log(n))
# best case performance: O(1)
if x[x0] > range.left():
x0 = np.searchsorted(x, range.left()) - 1*ds
x0 = np.clip(x0, a_min=0, a_max=len(x))
if x[x1] < range.right():
x1 = np.searchsorted(x, range.right()) + 2*ds
x1 = np.clip(x1, a_min=0, a_max=len(x))
x = x[x0:x1]
y = y[x0:x1]
if ds > 1:
if self.opts['downsampleMethod'] == 'subsample':