np.diff on boolean arrays now raises
There is an ongoing discussion on github: https://github.com/numpy/numpy/issues/9251 In 1.13 np.diff has started raising on boolean arrays, since subtraction of boolean arrays is now deprecated. A decision has to be made whether: - raising an error is the correct thing to do, and only the docstring needs updating, or - backwards compatibility is more important and diff should still work on boolean arrays. If you have opinions on the subject, or enjoy arguing for the sake of it, please share your thoughts either here or on github. Thanks! -- (\__/) ( O.o) ( > <) Este es Conejo. Copia a Conejo en tu firma y ayúdale en sus planes de dominación mundial.
On Thu, Jun 15, 2017 at 7:08 PM, Jaime Fernández del Río < jaime.frio@gmail.com> wrote:
The issue is bigger than np.diff. For example, there's a problem with the scipy.ndimage morphology functions ( https://github.com/scipy/scipy/issues/7493) that looks pretty serious. All ndimage.binary_* functions (7 of them) for example return boolean arrays, and chaining those is now broken. Unfortunately it seems that that wasn't covered by the ndimage test suite. Possibly reverting the breaking change in 1.13.1 is the best way to fix this. Ralf
On Thu, 2017-06-15 at 22:35 +1200, Ralf Gommers wrote:
Sure, I would say there is nothing wrong with reverting for now (and it simply is the safe and easy way). Though it would be good to address the issue of what should happen in the future with diff (and possibly the subtract deprecation itself). If we stick to it, but its necessary, we could delay the deprecation and make it a VisibleDeprecationWarning. - Sebastian
On Thu, Jun 15, 2017 at 4:35 AM, Ralf Gommers <ralf.gommers@gmail.com> wrote:
There were two related deprecations of boolean operators: subtraction and negative. I haven't heard any complaints about the second, which I think is less controversial, but I think reversion is the way to go for subtraction, at least for 1.13.1. The main virtue of the deprecations is clarity, xor is more informative when applied to boolean values than `-`, although the latter is certainly correct in F_2. Chuck
On Thu, Jun 15, 2017 at 6:16 AM, Charles R Harris <charlesr.harris@gmail.com
wrote:
See reversion at https://github.com/numpy/numpy/pull/9255. Chuck
On Thu, Jun 15, 2017 at 7:08 PM, Jaime Fernández del Río < jaime.frio@gmail.com> wrote:
The issue is bigger than np.diff. For example, there's a problem with the scipy.ndimage morphology functions ( https://github.com/scipy/scipy/issues/7493) that looks pretty serious. All ndimage.binary_* functions (7 of them) for example return boolean arrays, and chaining those is now broken. Unfortunately it seems that that wasn't covered by the ndimage test suite. Possibly reverting the breaking change in 1.13.1 is the best way to fix this. Ralf
On Thu, 2017-06-15 at 22:35 +1200, Ralf Gommers wrote:
Sure, I would say there is nothing wrong with reverting for now (and it simply is the safe and easy way). Though it would be good to address the issue of what should happen in the future with diff (and possibly the subtract deprecation itself). If we stick to it, but its necessary, we could delay the deprecation and make it a VisibleDeprecationWarning. - Sebastian
On Thu, Jun 15, 2017 at 4:35 AM, Ralf Gommers <ralf.gommers@gmail.com> wrote:
There were two related deprecations of boolean operators: subtraction and negative. I haven't heard any complaints about the second, which I think is less controversial, but I think reversion is the way to go for subtraction, at least for 1.13.1. The main virtue of the deprecations is clarity, xor is more informative when applied to boolean values than `-`, although the latter is certainly correct in F_2. Chuck
On Thu, Jun 15, 2017 at 6:16 AM, Charles R Harris <charlesr.harris@gmail.com
wrote:
See reversion at https://github.com/numpy/numpy/pull/9255. Chuck
participants (4)
-
Charles R Harris -
Jaime Fernández del Río -
Ralf Gommers -
Sebastian Berg