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How do you calculate program run time in python? [duplicate]
...cript, you can run it under time on a unix-like system.
kotai:~ chmullig$ cat sleep.py
import time
print "presleep"
time.sleep(10)
print "post sleep"
kotai:~ chmullig$ python sleep.py
presleep
post sleep
kotai:~ chmullig$ time python sleep.py
presleep
post sleep
real 0m10.035s
user 0m0.0...
python .replace() regex [duplicate]
...ub(regex_search,regex_replace,contents)
– Walrus the Cat
Feb 2 '15 at 18:54
4
...
Is there a way to “limit” the result with ELOQUENT ORM of Laravel?
...
Also, we can use it following ways
To get only first
$cat_details = DB::table('an_category')->where('slug', 'people')->first();
To get by limit and offset
$top_articles = DB::table('an_pages')->where('status',1)->limit(30)->offset(0)->orderBy('id', 'DESC')->...
Linux Glibc幽灵漏洞允许黑客远程获取系统权 - 操作系统(内核) - 清泛网 - ...
...ux发行版本。
漏洞检测方法
请自行检测：
[[test]] $ cat > GHOST.c << EOF #include <netdb.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <errno.h> #define CANARY"in_the_coal_mine" struct { char buffer[1024]; char canary[sizeof(CANARY)]; } temp = { "buffe...
Which version of CodeIgniter am I currently using?
...
In newer versions CodeIgniter.php is located in /system/core folder.
– z-boss
Jul 14 '11 at 3:08
...
How to import multiple .csv files at once?
...nto one file.
In Unix, if the files had no headers, then its as easy as:
cat *.csv > all.csv
or if there are headers, and you can find a string that matches headers and only headers (ie suppose header lines all start with "Age"), you'd do:
cat *.csv | grep -v ^Age > all.csv
I think in W...
count the frequency that a value occurs in a dataframe column
...oupby.html
Also value_counts() as @DSM has commented, many ways to skin a cat here
In [38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupb...
How to modify a global variable within a function in bash?
...then add a variable? You definitively do not want to alter all the 1000 locations where a call to d is involved.
So leave the x away, so we can write:
_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }
d() { let x++; output=$(date +%Y%m%d-%H%M%S); _passback output ...
Is there a better way to express nested namespaces in C++ within the header
...R_EXPAND(VA_COUNT_HELPER(__VA_ARGS__, 6, 5, 4, 3, 2, 1))
#define VA_SELECT_CAT(_Name, _Count, ...) VA_HELPER_EXPAND(_Name##_Count(__VA_ARGS__))
#define VA_SELECT_HELPER(_Name, _Count, ...) VA_SELECT_CAT(_Name, _Count, __VA_ARGS__)
#define VA_SELECT(_Name, ...) VA_SELECT_HE...
What is the difference between LR, SLR, and LALR parsers?
...ing that GLR parsers can parse any context free language, using more complicated machinery but exactly the same tables (including the smaller version used by LALR). This means that GLR is strictly more powerful than LR, LALR and SLR; pretty much if you can write a standard BNF grammar, GLR will pars...