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How to execute Python scripts in Windows?
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In Win10 I write test.py 123 and I get 123 printed as sys.argv[1]. Did Microsoft changed something?
– Hrvoje T
Mar 28 '18 at 6:39
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printf() formatting for hex
... output is 0XC68491C0, not 0x43A66C31C68491C0
– 123iamking
May 7 '16 at 4:16
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Does every Javascript function have to return a value?
...s) to return void:
void noReturn()//return type void
{
printf("%d\n", 123);
return;//return nothing, can be left out, too
}
//in JS:
function noReturn()
{
console.log('123');//or evil document.write
return undefined;//<-- write it or not, the result is the same
return;//<...
Is JavaScript an untyped language?
...licit compiler interjection, the instruction will error during run-time.
"12345" * 1 === 12345 // string * number => number
Strongly typed means there is a compiler, and it wants you an explicit cast from string to integer.
(int) "12345" * 1 === 12345
In either case, some compiler's featur...
How to measure time taken by a function to execute
...returns the number of microseconds in the fractional (e.g. a value of 1000.123 is 1 second and 123 microseconds).
now() is monotonically increasing. This is important as Date.getTime() can possibly jump forward or even backward on subsequent calls. Notably, if the OS's system time is updated (e.g....
Which is the preferred way to concatenate a string in Python?
... to a string, then to a list:
a += b:
0.10780501365661621
a.append(b):
0.1123361587524414
OK, turns out that even when the resulting string is a million characters long, appending was still faster.
Now let's try with appending a thousand character long string a hundred thousand times:
a += b:
0...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
Is there any difference between GROUP BY and DISTINCT
...ukas Eder
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Python strptime() and timezones?
...mitation of that lib. >>> parser.parse("Thu, 25 Sep 2003 10:49:41,123 -0300") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/Users/wanghq/awscli/lib/python2.7/site-packages/dateutil/parser.py", line 748, in parse return DEFAUL...
Selecting data frame rows based on partial string match in a column
... 4 140.8 95 3.92 3.15 22.9 1 0 4 2
# Merc 280 19.2 6 167.6 123 3.92 3.44 18.3 1 0 4 4
# Merc 280C 17.8 6 167.6 123 3.92 3.44 18.9 1 0 4 4
# Merc 450SE 16.4 8 275.8 180 3.07 4.07 17.4 0 0 3 3
# Merc 450SL 17.3 8 275.8 180 3.07 3.73 17.6 0 0 3 ...