python-2.x

This is possible in python2: None < float('-inf') Also, it always returns True However, on python3, this throws TypeError: unorderable types: NoneType() < int() Why is None comparable to integers/floats with python2? Are there any benefits or applications to None being orderable in python2? First of all Python 2 allowed comparing all types of mixed types. This wart was fixed in Python 3 eventually. CPython implementation detail : Objects of different types except numbers are ordered by their type names; objects of the same types that don’t support proper comparison are ordered by their address

I'm trying to resize an image to 500x500px but got this error: File "C:\Python27\lib\site-packages\PIL\Image.py", line 1681, in save save_handler = SAVE[format.upper()] KeyError: 'JPG' This is the code: from PIL import Image img = Image.open('car.jpg') new_img = img.resize((500,500)) new_img.save('car_resized','jpg') You need to set the format parameter in your call to the save function to 'JPEG': from PIL import Image img = Image.open('car.jpg') new_img = img.resize((500,500)) new_img.save("car_resized.jpg", "JPEG", optimize=True) Here is the solution: from PIL import Image img = Image.open(

Python 3.0 is in beta with a final release coming shortly. Obviously it will take some significant time for general adoption and for it to eventually replace 2.x. I am writing a tutorial about certain aspects of programming Python. I'm wondering if I should do it in Python 2.x or 3.0? (not that the difference is huge) a 2.x tutorial is probably more useful now, but it would be nice to start producing 3.0 tutorials. anyone have thoughts? (of course I could do both, but I would prefer to do one or the other) Start with 2.x. Most existing libraries will be on 2.x for a long time. Last year, Guido

In console when I'm trying output Russian characters It gives me ??????????????? Who know why? I tried write to file - in this case the same situation. for example f=open('tets.txt','w') f.write('some russian text') f.close inside file is - ?????????????????????????/ or p="some russian text" print p ????????????? In additional Notepad don't allow me to save file with Russian letters. I give this: This file contains characters in Unicode format which will be lost if you save this file as an ANSI encoded text file. To keep the Unicode information, click Cancel below and then select one of the

I have an array that I am viewing using imshow() . (imsave() really, but the process should be identical). I know that the values in the array will be between 0-9 and wonder if it is possible to use cmap to set each output to a specific 'color'. Perhaps by mapping these to a dict? Just use a ListedColormap . As a quick (but ugly) example: import matplotlib.pyplot as plt from matplotlib.colors import ListedColormap cmap = ListedColormap(['red', 'green', 'blue', 'black'], 'indexed') fig, ax = plt.subplots() im = ax.imshow([range(4)], interpolation='none', cmap=cmap) fig.colorbar(im) plt.show()

Is there a way, given a simple Class, to output all the possible attributes for it? Standard attributes like __class__ and __doc__ and special read only attributes like __mro__ , __bases__ et al. Generally, all present attributes? Considering the most simplistic case for a Class: class myClass: pass The dir() , vars() and inspect.getmembers() all exclude certain builtin attributes. The most complete list is offered by using myClass.__dir__(MyClass) which, while adding built in attributes, excludes user defined attributes of MyClass , for example: In [3]: set(MyClass.__dir__(MyClass)) - set(dir