Dataframe returning empty after assignment of values?-CodePudding

Essentially, I would like to add values to certain columns in an empty DataFrame with defined columns, but when I run the code, I get.

Empty DataFrame
Columns: [AP, AV]
Index: []

Code:

df = pd.DataFrame(columns=['AP', 'AV'])  
df['AP'] = propName 
df['AV'] = propVal

I think this could be a simple fix, but I've tried some different solutions to no avail. I've tried adding the values to an existing dataframe I have, and it works when I do that, but would like to have these values in a new, separate structure.

Thank you,

CodePudding user response：

df = pd.DataFrame({'AP': [propName]})
df['AV'] = propVal
print(df)

df = pd.DataFrame({'AP': [123, 233], 'AV': [345, 777]})

It's probably better to initialize with empty values:

df = pd.DataFrame({'AP' : [np.nan], 'AV': [np.nan]})
df['AP'] = 12345
df['AV'] = 12345
print(df)

CodePudding user response：

Assign propName and propValue to dictionary:

dict = {}
dict[propName] = propValue

Then, push to empty DataFrame, df:

df = pd.DataFrame()
df['AP'] = dict.keys()
df['AV'] = dict.values()

Probably not the most elegant solution, but works great for me.