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str performance in python
...; import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
6 CALL_FUNCTION 1
9 RETURN_VALUE
>>> dis.dis(lambda: '%s' % 100000)
9 0 LOAD...
Getting JavaScript object key list
... answered Jun 18 '10 at 9:32
zed_0xffzed_0xff
28.2k77 gold badges4747 silver badges7070 bronze badges
...
Learning Python from Ruby; Differences and Similarities
...at to the collection each method (if list supported this method):
def some_operation(value):
...
collection.each(some_operation)
That doesn't flow very nicely. So, typically the following non-functional approach would be used in Python:
for value in collection:
...
Using resources in a sa...
How do I execute a string containing Python code in Python?
....stderr = codeErr
exec code
# restore stdout and stderr
sys.stdout = sys.__stdout__
sys.stderr = sys.__stderr__
print f(4)
s = codeErr.getvalue()
print "error:\n%s\n" % s
s = codeOut.getvalue()
print "output:\n%s" % s
codeOut.close()
codeErr.close()
...
Guaranteed lifetime of temporary in C++?
... a "full-expression" in this case: printf("%s", strdup(std::string("$$$").c_str()) ); ?I mean if strdup(std::string("$$$").c_str()) is taken as the full expression, then the pointer that strdup sees is valid. If std::string("$$$").c_str() is a full expression, then the pointer that strdup sees is in...
When should you use constexpr capability in C++11?
...lues over and over?
int func (int n) {
static std::map<int, int> _cached;
if (_cached.find (n) == _cached.end ())
_cached[n] = n > 0 ? n + func (n-1) : n;
return _cached[n];
}
The result
By introducing your silly optimization, you just broke every usage of your function th...
How to send an email with Gmail as provider using Python?
... line and use CRLF as EOL markers.
E.g.
msg = "\r\n".join([
"From: user_me@gmail.com",
"To: user_you@gmail.com",
"Subject: Just a message",
"",
"Why, oh why"
])
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Oracle “(+)” Operator
...e a link at the official Oracle documentation: docs.oracle.com/html/A95915_01/sqopr.htm
– Vargan
Jun 3 '15 at 16:55
...
Drop all tables whose names begin with a certain string
...RE @cmd varchar(4000)
DECLARE cmds CURSOR FOR
SELECT 'drop table [' + Table_Name + ']'
FROM INFORMATION_SCHEMA.TABLES
WHERE Table_Name LIKE 'prefix%'
OPEN cmds
WHILE 1 = 1
BEGIN
FETCH cmds INTO @cmd
IF @@fetch_status != 0 BREAK
EXEC(@cmd)
END
CLOSE cmds;
DEALLOCATE cmds
This is cleane...
Group by multiple columns in dplyr, using string vector input
...
Since this question was posted, dplyr added scoped versions of group_by (documentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = s...