Pandas KeyError: value not in index

Question

I have the following code,

df = pd.read_csv(CsvFileName)

p = df.pivot_table(index=[\'Hour\'], columns=\'DOW\', values=\'Changes\', aggfunc=np.mean).round(0         


        

Answer 1

I had the same issue.

During the 1st development I used a .csv file (comma as separator) that I've modified a bit before saving it. After saving the commas became semicolon.

On Windows it is dependent on the "Regional and Language Options" customize screen where you find a List separator. This is the char Windows applications expect to be the CSV separator.

When testing from a brand new file I encountered that issue.

I've removed the 'sep' argument in read_csv method before:

df1 = pd.read_csv('myfile.csv', sep=',');

after:

df1 = pd.read_csv('myfile.csv');

That way, the issue disappeared.