Bizarre np.linalg.norm error about rdp HOT 6 CLOSED

On Mon, Nov 28, 2016 at 9:01 PM Fabian Hirschmann ***@***.***> wrote: Hi hardmaru, I have seen that error before, but I was unable to pinpoint the root cause. Do you know what the input data in that case looked like? Is it possible that it was an empty array? You can also try if it works with an older version: https://pypi.python.org/packages/6c/4e/7ab95aad0a39c5d938014344cc321be6012b4156226d04ab3803b759a35c/rdp-0.6.tar.gz#md5=0e5de170f1322ef2d9e390a4502b5d0e If that works it may be a regression bug. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#6 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AGBoHsBREbJFOv-o-g6d6-mjwxMrsfzGks5rC0EegaJpZM4K8zWG> .

On Dec 2, 2016 11:56 AM, "hardmaru" ***@***.***> wrote: Hi fhirschmann, It seems that is the case. An example of a line where rdp was breaking is: line = [[53, 90],[52, 89],[51, 89],[50, 89],[50, 90],[50, 91],[52, 91],[56, 91],[56, 90],[55, 90],[54, 90],[53, 90]] If I use the pl_dist in the older version, and rename it pldist_old def pldist_old(x0, x1, x2): """ Calculates the distance from the point ``x0`` to the line given by the points ``x1`` and ``x2``. :param x0: a point :type x0: a 2x1 numpy array :param x1: a point of the line :type x1: 2x1 numpy array :param x2: another point of the line :type x2: 2x1 numpy array """ if x1[0] == x2[0]: return np.abs(x0[0] - x1[0]) return np.divide(np.linalg.norm(np.linalg.det([x2 - x1, x1 - x0])), np.linalg.norm(x2 - x1)) After I call rdp(line, epsilon=0.99, dist=pldist_old), we can now get reduced line: [[53, 90], [50, 89], [50, 91], [56, 91], [53, 90]] But if we call rdp(line, epsilon=0.99, dist=pldist), the error pops up: ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all() I'm not sure the best way to get this back into your code, but it's very helpful to have resolved this! Cheers. — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#6 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAAvqI_ruZpgjdBhcP5y2S3-6rek0Cqaks5rD_l6gaJpZM4K8zWG> .

Hi, Thanks for providing a failing example. I'll be at NIPS next week and will, hence, look into this the week after next week. On Dec 2, 2016 11:56 AM, "hardmaru" ***@***.***> wrote: > Hi fhirschmann, > > It seems that is the case. An example of a line where rdp was breaking is: > > line = [[53, 90],[52, 89],[51, 89],[50, 89],[50, 90],[50, 91],[52, 91],[56, 91],[56, 90],[55, 90],[54, 90],[53, 90]] > > If I use the pl_dist in the older version, and rename it pldist_old > > def pldist_old(x0, x1, x2): > """ > Calculates the distance from the point ``x0`` to the line given > by the points ``x1`` and ``x2``. > > :param x0: a point > :type x0: a 2x1 numpy array > :param x1: a point of the line > :type x1: 2x1 numpy array > :param x2: another point of the line > :type x2: 2x1 numpy array > """ > if x1[0] == x2[0]: > return np.abs(x0[0] - x1[0]) > > return np.divide(np.linalg.norm(np.linalg.det([x2 - x1, x1 - x0])), > np.linalg.norm(x2 - x1)) > > After I call rdp(line, epsilon=0.99, dist=pldist_old), we can now get > reduced line: > > [[53, 90], [50, 89], [50, 91], [56, 91], [53, 90]] > > But if we call rdp(line, epsilon=0.99, dist=pldist), the error pops up: > > ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all() > > I'm not sure the best way to get this back into your code, but it's very > helpful to have resolved this! > > Cheers. > > — > You are receiving this because you commented. > Reply to this email directly, view it on GitHub > <#6 (comment)>, or mute > the thread > < https://github.com/notifications/unsubscribe-auth/AAAvqI_ruZpgjdBhcP5y2S3-6rek0Cqaks5rD_l6gaJpZM4K8zWG > > . > — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#6 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AGBoHiUWE6Z3P2IMEw4-4RtI6lgfBXd3ks5rEGJ6gaJpZM4K8zWG> .