I just picked up Pandas to do with some data analysis work in my biology research. Turns out one of the proteins I'm analyzing is called 'NA'.
I have a matrix with pairwise 'HA, M1, M2, NA, NP...' on the column headers, and the same as "row headers" (for the biologists who might read this, I'm working with influenza).
When I import the data into Pandas directly from a CSV file, it reads the "row headers" as 'HA, M1, M2...' and then NA gets read as NaN. Is there any way to stop this? The column headers are fine - 'HA, M1, M2, NA, NP etc...'
Turn off NaN detection this way: pd.read_csv(filename, keep_default_na=False)
I originally suggested na_filter=False, which gets the job done. But, if I understand Jeff's comments below, this is a cleaner solution.
Example:
In [1]: pd.read_csv('test')
Out[1]:[4]: pd.read_csv('test', keep_default_na=False)
Out[4]:1 2
2 3
Just ran into this issue--I specified a str converter for the column instead, so I could keep na elsewhere:
pd.read_csv(... , converters={ "file name": str, "company name": str})
来源：https://stackoverflow.com/questions/16596188/pandas-convert-na-to-nan