如何按列和行遍历数据表？

Question

I want to calculate growth for a data table.

I am stuck on iterating through the rows and columns.

DF:

City ...... year(2001) ... 2002 ... 2003
New York... 20.0.... 24.1 ... 28.7
Los Angeles.11.1.... 12.1 ... 13.1

New Table:

City ...... 2001 ... 2002 ... 2003
New York... nan....  0.20 ...  0.19
Los Angeles.nan....  0.10 ...   0.8

Code:

for row in range(len(import_table)):
  for i in column_list:
    if i == "_2000":
         pass
    else:
        calculated_growth =  import_table.iloc[i].sub(import_table.iloc[i-1])
      ## update new DF ##
  column_calc_position = column_calc_position + 1

This is a lot harder in python than it seems. I'm teaching myself data science by re-coding something I wrote in VBA (and Excel).

Answer 1

Iterate through rows:

for row in df.rows:
   print(row['2001'], row['2002'])

Iterate through column:

for column in df:
    print(df[column])