Efficiently sorting a numpy array in descending order?
temp[::-1].sort() sorts the array in place, whereas np.sort(temp)[::-1] creates a new array.
Python
What is the Python equivalent of Matlab’s tic and toc functions?
Apart from timeit which ThiefMaster mentioned, a simple way to do it is just (after importing time): I have a helper class I like to use: It can be used as a context manager: Sometimes I find this technique more convenient than timeit – it all depends on what you want to measure.
bash: mkvirtualenv: command not found
Solution 1: For some reason, virtualenvwrapper.sh installed in /usr/bin/virtualenvwrapper.sh, instead of under /usr/local/bin. The following in my .bash_profile works… My install seems to work fine without sourcing virtualenvwrapper_bashrc Solution 2: Alternatively as mentioned below, you could leverage the chance that virtualenvwrapper.sh is already in your shell’s PATH and just issue a source `which virtualenvwrapper.sh`
NameError: global name ‘unicode’ is not defined – in Python 3
Python 3 renamed the unicode type to str, the old str type has been replaced by bytes. You may want to read the Python 3 porting HOWTO for more such details. There is also Lennart Regebro’s Porting to Python 3: An in-depth guide, free online. Last but not least, you could just try to use the 2to3 tool to see how that translates the code for you.
RuntimeError: Invalid DISPLAY variable
You must declare matplotlib.use(‘agg’) before import pylab as plt. Reference
Matplotlib: TypeError: can’t multiply sequence by non-int of type ‘numpy.float64’
You should make x and y numpy arrays, not lists: With this change, it produces the expected plot. If they are lists, m * x will not produce the result you expect, but an empty list. Note that m is anumpy.float64 scalar, not a standard Python float. I actually consider this a bit dubious behavior of Numpy. In normal Python, multiplying a list with an … Read more
Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
Just ran into this problem. I don’t know if it’s the same thing that hit your code, but for me the root cause was because I forgot to put name= on the last argument of the url (or path in Django 2.0+) function call. For instance, the following functions throw the error from the question: But these actually work: The reason … Read more
UnicodeEncodeError: ‘charmap’ codec can’t encode characters
I fixed it by adding .encode(“utf-8”) to soup. That means that print(soup) becomes print(soup.encode(“utf-8”)).
Unsupported operation :not writeable python
You open the variable “file” as a read only then attempt to write to it: Instead, use the ‘w’ flag.
ModuleNotFoundError: No module named ‘seaborn’ in Python IDE
In PyCharm IDE, we can import the downloaded libraries, and that’s what I did. Still, I have no clue on how to resolve this issue on Python IDE, but as of now, it’s working on PyCharm for me.