New to Programming: Adding custom functions with ipynotify classes
Dave Angel
davea at davea.name
Fri Apr 3 08:12:38 EDT 2015
On 04/03/2015 07:37 AM, Steven D'Aprano wrote:
> On Fri, 3 Apr 2015 12:30 pm, Saran A wrote:
>
>> #This helper function returns the length of the file
>> def file_len(f):
>> with open(f) as f:
>> for i, l in enumerate(f):
>> pass
>> return i + 1
>
> Not as given it doesn't. It will raise an exception if the file cannot be
> opened, and it will return 1 for any file you can read.
>
> After you fix the incorrect indentation, the function is horribly
> inefficient. Instead, use this:
>
> import os
> os.stat(filename).st_size
>
>
No, he actually wants the number of records in the file. So he still
needs to read the whole file.
Naturally I figured that out from the phrase in the spec:
"indicating the total number of records processed"
not from the comment in the code.
--
DaveA
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