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How to use glob() to find files recursively?
...les in the current directory or hidden files on Unix based system, use the os.walk solution below.
os.walk
For older Python versions, use os.walk to recursively walk a directory and fnmatch.filter to match against a simple expression:
import fnmatch
import os
matches = []
for root, dirnames, filena...
How to create a zip archive of a directory in Python?
...s easiest to explain with some example code:
#!/usr/bin/env python
import os
import zipfile
def zipdir(path, ziph):
# ziph is zipfile handle
for root, dirs, files in os.walk(path):
for file in files:
ziph.write(os.path.join(root, file))
if __name__ == '__main__':
z...
Remove duplicated rows using dplyr
...ction for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_nu...
How to find out the number of CPUs using python
...
On Python 3.6.2 I could only use os.cpu_count()
– Achilles
Sep 11 '17 at 19:59
...
Checking if a string can be converted to float in Python
... ------------
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")) ...
Python: What OS am I running on?
...
>>> import os
>>> os.name
'posix'
>>> import platform
>>> platform.system()
'Linux'
>>> platform.release()
'2.6.22-15-generic'
The output of platform.system() is as follows:
Linux: Linux
Mac: Darw...
What is an OS kernel ? How does it differ from an operating system? [closed]
...System while for a programmer the Linux kernel itself is a perfectly valid OS depending on what you're trying to achieve. For instance embedded systems are mostly just kernel with very small number of specialized processes running on top of them. In that case the kernel itself becomes the OS itself....
Append to a file in Go
...
This answers works in Go1:
f, err := os.OpenFile(filename, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
if err != nil {
panic(err)
}
defer f.Close()
if _, err = f.WriteString(text); err != nil {
panic(err)
}
...
Dynamic SQL - EXEC(@SQL) versus EXEC SP_EXECUTESQL(@SQL)
...
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
...
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
4
# 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
9
...