how to make existing dataframe empty in python code example

Example 1: empty dataframe

newDF = pd.DataFrame() #creates a new dataframe that's empty
newDF = newDF.append(oldDF, ignore_index = True) # ignoring index is optional
# try printing some data from newDF
print newDF.head() #again optional

Example 2: create empty pandas dataframe

df = pd.DataFrame(columns=['a', 'b', 'c'])