Trying to search and make new column from the keyword.

[deanhystad]

The error says that you have a float number in df1 which means you have a float number in qd1. From the screenshot this must be between rows 4 and 73511. The code below has the same problem, crashing when it tries to call (2.0).upper().

import pandas as pd

df1 = pd.DataFrame(["-", "+", "1", 2.0], columns=["CRTXT"])
for x in df1['CRTXT']:
    print(x, ', ', sep="", end="")
    print(x.upper())

Output:
-, -
+, +
1, 1
2.0, Traceback (most recent call last):
  File "...", line 6, in <module> 
    print(x.upper())
AttributeError: 'float' object has no attribute 'upper'