Hi Erik, I believe this is the same issue reported here: https://github.com/pyqtgraph/pyqtgraph/issues/1033
The comments there are still accurate (fixed version not released yet), but there are instructions for installing pyqtgraph via git. Hope that helps. - Kenny On Saturday, November 23, 2019 at 2:29:56 PM UTC-8, Erik J wrote: > > > > On Saturday, November 23, 2019 at 3:27:05 PM UTC-7, Erik J wrote: >> >> Hi everyone, >> >> I am using a HistogramLutWidget for an image that is displayed in a >> pg.GraphicsLayoutWidget. The image is a dark and gain corrected image from >> a CCD camera that updates in real time as it is received from the camera. >> The problem I am having is that the ImageItem in the histogram display will >> crash periodically in the method getHistogram(). This occurs if the min and >> max of the image are the same. Here is the code snippet from getHistogram: >> >> if bins == 'auto': >> if stepData.dtype.kind in "ui": >> mn = stepData.min() >> mx = stepData.max() >> step = np.ceil((mx-mn) / 500.) >> bins = np.arange(mn, mx+1.01*step, step, dtype=np.int) >> if len(bins) == 0: >> bins = [mn, mx] >> else: >> bins = 500 >> >> If mn and mx are equal, then np.arange() fails with an error. I suggest >> the following code change to fix the problem: >> if bins == 'auto': >> if stepData.dtype.kind in "ui": >> mn = stepData.min() >> mx = stepData.max() >> step = np.ceil((mx-mn) / 500.) >> >> bins = np.arange(mn, mx+1.01*step, step, dtype=np.int) >> if len(bins) == 0: >> bins = [mn, mx] >> else: >> bins = 500 >> >> >> Sorry, somehow this got posted before I was finished. The new code should >> be: >> > > if bins == 'auto': > if stepData.dtype.kind in "ui": > mn = stepData.min() > mx = stepData.max() > step = np.ceil((mx-mn) / 500.) > if step == 0: step = 1.0 > bins = np.arange(mn, mx+1.01*step, step, dtype=np.int) > if len(bins) == 0: > bins = [mn, mx] > else: > bins = 500 > > > Please let me know if anyone else has experienced this problem. It can > easily occur if an image is saturated or if nearly all the pixels are zero. > > Thanks, > Erik > > -- You received this message because you are subscribed to the Google Groups "pyqtgraph" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/pyqtgraph/d6dfc5ad-8fda-45ab-9531-81f84fa5a89b%40googlegroups.com.
