Python - Remove entire Line in file using specific data

Question

I'm here because i exhausted all my resources to built this program...

I want to delete a line of a file using specific data like this

Code \\t Name \\t Colum2 \\t Colum3 \\t Colum4 \\t Colum5 \\n

I want to delete entire line based on Code

if i type the code, the *.py will search the line thats contains this string and will delete it.

Can any good soul help me?

Answer 1

Assuming the following input (generated on generatedata.com ) and saved as input.txt:

1    Jennifer O. Ingram    P.O. Box 724, 4252 Arcu. St.
2    Lacy N. Fields    5998 Scelerisque Road
3    Blythe P. Abbott    Ap #251-2931 Magna. Rd.
4    Alyssa Y. Cobb    438-8110 Enim. Rd.
5    Peter Z. May    Ap #271-8340 Eget Avenue
6    MacKenzie A. Santos    8366 Nunc. St.
7    Kevyn C. Willis    Ap #583-9635 Erat Avenue
8    Nissim E. Ward    7606 Duis Rd.
9    Duncan J. Armstrong    Ap #164-282 Id, St.
10    Jesse B. Barnett    P.O. Box 742, 5758 Sagittis Street

the following code will remove line with code 5:

# Declare which code you want to delete.
# This can be further improved by being a parameter
# or read from outside the script.
code = 5
removed_lines = 0
f = open("input.txt","r+")
lines = f.readlines()
f.seek(0)
for line in lines:
    # Writes to the file all the lines except for those that
    # begin with the code declared above.
    if not line.startswith(str(code)):
        f.write(line)
    else:
        print("removed line %s" % line)
        removed_lines += 1
f.truncate()
f.close()
print("%d lines were removed" % removed_lines)

and input.txt will be:

1    Jennifer O. Ingram    P.O. Box 724, 4252 Arcu. St.
2    Lacy N. Fields    5998 Scelerisque Road
3    Blythe P. Abbott    Ap #251-2931 Magna. Rd.
4    Alyssa Y. Cobb    438-8110 Enim. Rd.
6    MacKenzie A. Santos    8366 Nunc. St.
7    Kevyn C. Willis    Ap #583-9635 Erat Avenue
8    Nissim E. Ward    7606 Duis Rd.
9    Duncan J. Armstrong    Ap #164-282 Id, St.
10    Jesse B. Barnett    P.O. Box 742, 5758 Sagittis Street

If the files are large, the run of the script can take more time and resources.

Answer 2

You can read the file and then open it in write mode, and only write the lines that don't have that code in the beginning.

//Open in read mode
f = open("yourfile.txt","r")
lines = f.readlines()
f.close()
//if code is 8
code = 8 
//Open in write mode
f = open("yourfile.txt","w")

for line in lines:
  arr = line.split('\t')
  if arr[0]!=code:   //Check for the code to avoid
    f.write(line)

f.close()