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Checking if a string can be converted to float in Python
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print(isfloat("")) False
print(isfloat("1234567")) True
print(isfloat("NaN")) True nan is also float
print(isfloat("NaNananana BATMAN")) False
print(isfloat("123.456")) True
print(isfloat("123.E4")) ...
how to check if a file is a directory or regular file in python? [duplicate]
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os.path.isfile("bob.txt") # Does bob.txt exist? Is it a file, or a directory?
os.path.isdir("bob")
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How to check whether a file is empty or not?
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>>> import os
>>> os.stat("file").st_size == 0
True
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Copy multiple files in Python
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You can use os.listdir() to get the files in the source directory, os.path.isfile() to see if they are regular files (including symbolic links on *nix systems), and shutil.copy to do the copying.
The following code copies only the regul...
Dynamic SQL - EXEC(@SQL) versus EXEC SP_EXECUTESQL(@SQL)
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EXEC('SELECT * FROM FOO WHERE ID=?', 123) will replace the parameter placeholder "?" with the value 123 and then execute the query, returning a result for SELECT * FROM FOO WHERE ID=123
– Peter Wone
Jun 1 '10 at 23:27
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sed: print only matching group
...it with a 2nd grep.
# To extract \1 from /xx([0-9]+)yy/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'xx[0-9]+yy' | grep -Eo '[0-9]+'
123
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# To extract \1 from /a([0-9]+)b/
$ echo "aa678bb xx123yy xx4yy aa42 aa9bb" | grep -Eo 'a[0-9]+b' | grep -Eo '[0-9]+'
678
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What does the “yield” keyword do?
...one, etc. And generators return... well that's where yield comes in:
def f123():
yield 1
yield 2
yield 3
for item in f123():
print item
Instead of yield statements, if you had three return statements in f123() only the first would get executed, and the function would exit. But f1...
How do I add tab completion to the Python shell?
...g your .bashrc and .bash_profile as suggested at the bottom of this page: joshstaiger.org/archives/2005/07/bash_profile_vs.html It also provides information on the difference between them. It might not solve the issue, but it might help.
– Dangercrow
Oct 21 '16...
How can I find script's directory with Python? [duplicate]
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You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path:
import os
print(os.path.dirname(os.path.realpath(__file__)))
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How to find if directory exists in Python
In the os module in Python, is there a way to find if a directory exists, something like:
13 Answers
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