How to sum in a for loop in pandas DataFrame

Question

I am the beginner in pandas and am struggling with a for loop.

I loaded the following excel file to pandas:

x=pd.read_excel('BTC.xlsx',)
x

Here is what I get:

   BTC obtained
0   0.00567
1   0.00054
2   0.00230

I want to iterate the numbers using a for loop:

n=0
for v in x.iteritems():
    n+=v
    print(n)

When I run this, I always get the following error:

TypeError: unsupported operand type(s) for +=: 'int' and 'tuple'

Can someone please help me with this?

Answer 1

You could also use iterrows() for this like so:

df = pd.DataFrame({'BTC obtained':[0.00567,0.00054,0.00230]})
print(df)

n=0
for index, row in df.iterrows():
    n+=row["BTC obtained"]
    print(n)

Output

0.00567
0.006209999999999999
0.00851

Answer 2

If you see the documentation of iteritems, you will see that the command yields two things:

• label: object
• content: Series

That means that v will be a tuple (label, content). If you want to access the series you will have to access v[1].

Alternatively, you can do:

for label, v in x.iteritems():

Based on your comment, it seems like you want the cumulative summation of the elements. You can do this without a for loop, by using pandas cumsum:

n = x.cumsum()

If you want to use a for loop you can do the following:

n=0  
for label, v in x.iteritems():  
    n+=v['BTC obtained']  
    print(n)