Key error when selecting columns in pandas dataframe after read_csv
I’m trying to read in a CSV file into a pandas dataframe and select a column, but keep getting a key error.
python
Why aren’t Python sets hashable?
I stumbled across a blog post detailing how to implement a powerset function in Python. So I went about trying my own way of doing it, and discovered that Python apparently cannot have a set of sets, since set is not hashable. This is irksome, since the definition of a powerset is that it is a set of sets, and I wanted to implement it using actual set operations.
Javascript – No ‘Access-Control-Allow-Origin’ header is present on the requested resource
I need to send data through XmlHttpRequest from JavaScript to Python server. Because I’m using localhost, I need to use CORS. I’m using the Flask framework and its module flask_cors.
Shift NaNs to the end of their respective rows
I have a DataFrame like :
Direct assignment to the forward side of a many-to-many set is prohibited. Use emails_for_help.set() instead
I am new to Django and didn’t find any reference regarding this issue. I am getting this error when i use many to many field in Django model (models.py). I guess the issue is assigning m2m field in view(views.py) from form(forms.py).
Splitting a number into the integer and decimal parts
Is there a pythonic way of splitting a number such as 1234.5678 into two parts (1234, 0.5678) i.e. the integer part and the decimal part?
Creating a new file, filename contains loop variable, python
I want to run a function over a loop and I want to store the outputs in different files, such that the filename contains the loop variable. Here is an example
determine matplotlib axis size in pixels
Given a set of axes in matplotlib, is there a way to determine its size in pixels? I need to scale things according to adjust for larger or smaller figures.
How can I update an attribute created by a base class’ mutable default argument, without modifying that argument?
This question already has answers here: Why does using `arg=None` fix Python’s mutable default argument issue? (5 answers) Closed last month. I’ve found a strange issue with subclassing and dictionary updates in new-style classes: Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)] on win32 >>> class a(object): … def __init__(self, props={}): … Read more
Add alpha to an existing matplotlib colormap
I’d like to make an overlay of several hexbin plots, but with builtin colormaps only the last one is visible. I don’t want to construct a colormap de novo. How one would add linear alpha to the colormap without knowing the inner structure of the colormap beforehand?