Basically trying to get an if else statement to work so that my data frame which is inside of a for loop gets updated (appended) with a new entry each time the for loop runs
psuedo code:
if df does not exist
df = some matrix
else
df1 = some new matrix
df1 = df1.append(df)
it just doesnt work; i think i have the wrong syntax
If the variable named df
literally does not exist, then this code will not work.
Initialize df
to some empty value at the beginning of your code, then check if it's empty:
df = None
... lots of code here, that possibly assigns df a value
if df:
do_something(df)
else:
df = something_else()
You need to add a colon(:) after if and else statement
if not df:
df = some matrix
else:
df1 = some new matrix
df1 = df1.append(df)
You have to set df to something to use it as a name in your if statement. Sensible empty values are None
and a dataframe with no rows. Let's assume the first.
import pandas
df = None
for i in range(100):
if df is None:
# Your default dataframe here.
# You probably want to set column names and types.
df = pandas.DataFrame()
# Instead of appending i, append your row.
df = df.append([i])
But then, you could obviously raise the if statement out of the for loop, which makes more sense.
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