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+--- Thread: Print the line before the corrent line (/thread-38726.html)
Print the line before the corrent line - tester_V - Nov-16-2022
Greetings!
I'm searching lines for two words "PASSED" and "FAILED"
I need to get the line before "PASSED" and the "FAILED" line.
I'm definitely doing it wrong,
the script I wrote does not get me the line I'm looking for, it actually prints the same line.
ftor = open('C:/01/prt.csv','r')
for num, el in enumerate(ftor, 1):
el=el.strip()
if 'PASSED' in el :
to_gt =num-1
print(f" BEFORE PASSED ->{to_gt} - {el}")
pas_fail = el.split(",")
print (f" {num} {pas_fail[9]} - {el}")
print("")
elif 'FAILED' in el :
to_gt =num-1
print(f" BEFORE FAILED ->{to_gt} - {el}")
pas_fail = el.split(",")
print (f" {num} {pas_fail[9]} - {el}")
print("")
ftor.close() Thank you!
RE: Print the line before the corrent line - deanhystad - Nov-16-2022
I don't understand your code, but if you just need to remember the last line for some reason:
prev_line = None
for line in file:
do stuff(line, prev_line)
prev_line = line
RE: Print the line before the corrent line - tester_V - Nov-16-2022
Awesome!
Thank you, guys!
RE: Print the line before the corrent line - Pedroski55 - Nov-17-2022
Are you guys all in the same class? I still have the csv sample from some other thread about finding "Failed"
The pass/fail column is column F
How big is your ftor?
import sys
path2csv = '/home/pedro/myPython/csv/csv/YE2531_20220609_074155_Tester1.csv'
with open(path2csv) as mycsv:
count = 1
data = mycsv.readlines()
print('The size of data is', sys.getsizeof(data))
fails = []
for line in data:
print('The size of line is', sys.getsizeof(line))
if 'Failed' in line:
print('line', count, 'failed')
print('of course, the previous line was', count-1)
fails.append(count)
count +=1
for f in fails:
print('fail line number is', f)
RE: Print the line before the corrent line - tester_V - Nov-17-2022
That is funny!
No, we are not in the same class for sure.
I'm a 61-year-old guy trying the get some data from machines...
It is hard to learn anything if you are that old...
RE: Print the line before the corrent line - Larz60+ - Nov-17-2022
Youngster!
RE: Print the line before the corrent line - tester_V - Nov-17-2022
Larz60+!
You are DA MAN
RE: Print the line before the corrent line - ndc85430 - Nov-17-2022
It's a shame you're on Windows. Otherwise, sounds like a job for
grep and head probably.
RE: Print the line before the corrent line - Pedroski55 - Nov-17-2022
I just asked if ftor is very big, maybe millions of lines, because then a function with yield may be better.
Then you need the experts here to design that, yield confuses me!
RE: Print the line before the corrent line - Gribouillis - Nov-18-2022
One can use
itertools.pairwise()for lineno, (prev_line, line) in enumerate(itertools.pairwise(ftor), 2):
... # do something with line and prev_line