Better to ‘try’ something and catch the exception or test if it’s possible first to avoid an exception?
Should I test if something is valid or just try to do it and catch the exception?
python
Replacing blank values (white space) with NaN in pandas
I want to find all values in a Pandas dataframe that contain whitespace (any arbitrary amount) and replace those values with NaNs.
How to make an immutable object in Python?
Although I have never needed this, it just struck me that making an immutable object in Python could be slightly tricky. You can’t just override __setattr__, because then you can’t even set attributes in the __init__. Subclassing a tuple is a trick that works:
Best way to join / merge by range in pandas
I’m frequently using pandas for merge (join) by using a range condition.
Appending the same string to a list of strings in Python
I am trying to take one string, and append it to every string contained in a list, and then have a new list with the completed strings. Example:
Pandas: rolling mean by time interval
I’ve got a bunch of polling data; I want to compute a Pandas rolling mean to get an estimate for each day based on a three-day window. According to this question, the rolling_* functions compute the window based on a specified number of values, and not a specific datetime range.
Why is a list comprehension so much faster than appending to a list?
I was wondering why list comprehension is so much faster than appending to a list. I thought the difference is just expressive, but it’s not.
Replace all elements of Python NumPy Array that are greater than some value
I have a 2D NumPy array and would like to replace all values in it greater than or equal to a threshold T with 255.0. To my knowledge, the most fundamental way would be:
Can pandas automatically read dates from a CSV file?
Today I was positively surprised by the fact that while reading data from a data file (for example) pandas is able to recognize types of values:
How to run multiple while loops at a time in Python
I’m trying to work on a simple Pygame program for a project that simply displays some faces and talks in a text to speech voice, but there is a while loop at the end that is necessary for the code to run but blocks another while loop that I need for the program from running. The while loop I’m trying to add uses time.sleep(), so if I try to put it into the same block as the first one which needs to be constantly running the program crashes. I’m sure I’m probably looking over something obvious but any help would be appreciated, thanks!