pytest-cache It seems to be a tool to cache func/args->result pairs and even persist them between testsuite-runs. Which seems like a great idea to speed things up. However I haven’t noticed any mention of automatically detecting a change of a function source code and invalidating corresponding cache …
Tag: python
pyplot combine multiple line labels in legend
I have data that results in multiple lines being plotted, I want to give these lines a single label in my legend. I think this can be better demonstrated using the example below, As you can see at Out[23] the plot resulted in 5 distinct lines. The resulting plot looks like this Is there any way that I can tel…
OperationalError, no such column. Django
I am going through the Django REST framework tutorial found at http://www.django-rest-framework.org/ I am almost finished with it and just added authentication. Now I am getting : I have looked in several places on the web, not just StackOverflow for the solution, it seems like in general that the problem is …
How To Mask Out Lower ‘x’ Bits of Python Integer Of Unknown Size
I am looking for a way to mask out (set to ‘0’) the lowest four bits of an integer in Python when I don’t know the total length of the number. If I knew the length of the integer beforehand I could just set the rest of the mask to 0xff, for instance if the integer would always be 32
SQLAlchemy: Logical Operators with case statement
Here is my mssql code snippet How would i use the and operator with case statement if i write the above statement in sqlalchemy. I have tried doing this but did not work I have searched through the sqlalchemy documentation but did not find the info on using logical operators with case statement. The link has …
How to return 0 with divide by zero
I’m trying to perform an element wise divide in python, but if a zero is encountered, I need the quotient to just be zero. For example: I could always just use a for-loop through my data, but to really utilize numpy’s optimizations, I need the divide function to return 0 upon divide by zero errors…
Python: DBSCAN in 3 dimensional space
I have been searching around for an implementation of DBSCAN for 3 dimensional points without much luck. Does anyone know I library that handles this or has any experience with doing this? I am assuming that the DBSCAN algorithm can handle 3 dimensions, by having the e value be a radius metric and the distanc…
Create celery tasks then run synchronously
My app gathers a bunch of phone numbers on a page. Once the user hits the submit button I create a celery task to call each number and give a reminder message then redirect them to a page where they can see the live updates about the call. I am using web sockets to live update the status of each
Pip build option to use multicore
I found that pip only use single core when it compiles packages. Since some python packages takes some time to build using pip, I’d like to utilize multicore on the machine. When using Makefile, I can do that like following command: How can I achieve same thing for pip? Answer From what I can tell it do…
Saving a video capture in python with openCV : empty video
I’m new in Python (2.7) and I try to work on video processing (with module openCv “cv2”). Starting with tutorials, I try to use the script of this tutorial : paragraph “Saving a video”. Everything works fine excepting that the video I’m saving is empty. I can find output.av…