This is my data frame attached in image and I want to sum as per the first column where ?? represent no value for that entry DATAFRAME IMAGE SAMPLE I want to write code to have an output like below HWK 0 CSP 0 DCF 0 I want to sum the values only if n/a or ?? occurs then ignore it and do the sum so that I can iterate through all the data frame for the same procedure
HWK 0
CSP ??
DCF 0
BM_IO ??
CS ??
os ??
CS 0
ESC 0
ESC 0
DCF 0
DLHLTL ??
CSP 0
CSP 0
ESC 0
CSP ??