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Check if a number is int or float
...
Use isinstance.
>>> x = 12
>>> isinstance(x, int)
True
>>> y = 12.0
>>> isinstance(y, float)
True
So:
>>> if isinstance(x, int):
print 'x is a int!'
x is a int!
_EDIT:_
As pointed out, in case of long integers, the above won't w...
Real life example, when to use OUTER / CROSS APPLY in SQL
...plus_one
FROM master..spt_values
CROSS APPLY (SELECT 2 * CAST(number AS BIGINT)) CA1(doubled_number)
CROSS APPLY (SELECT doubled_number + 1) CA2(doubled_number_plus_one)
4) Unpivoting more than one group of columns
Assumes 1NF violating table structure....
CREATE TABLE T
(
Id INT PR...
C++实现一款简单完整的聊天室服务器+客户端 - C/C++ - 清泛网 - 专注C/C++及内核技术
...息缓冲区，循环队列
char buf[MESSAGE_COUNT][MESSAGE_LENGTH];
int rear; //循环队列的队尾
int front; //循环队列的队首
public:
bool toStop;
//构造函数
MessageBuffer();
//析构函数
virtual ~MessageBuffer();
//将消息放入消息缓冲区...
Execution time of C program
...s, for example, gettimeofday is basically a wrapper for clock_gettime that converts nanoseconds to microseconds.
– Peter Cordes
Apr 5 '19 at 8:11
add a comment
...
What does “fragment” mean in ANTLR?
... to an inline function: It makes the grammar more readable and easier to maintain.
A fragment will never be counted as a token, it only serves to simplify a grammar.
Consider:
NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS;
fragment DIGITS: '1'..'9' '0'..'9'*;
fragment OCTAL_DIGITS: '0' '0'..'7'+;
fr...
What are “named tuples” in Python?
...u may just want to use a dictionary in this situation. Named tuples can be converted to dictionaries using pt1._asdict() which returns {'x': 1.0, 'y': 5.0} and can be operated upon with all the usual dictionary functions.
As already noted, you should check the documentation for more information f...
How to generate a range of numbers between two numbers?
...
an alternative solution is recursive CTE:
DECLARE @startnum INT=1000
DECLARE @endnum INT=1050
;
WITH gen AS (
SELECT @startnum AS num
UNION ALL
SELECT num+1 FROM gen WHERE num+1<=@endnum
)
SELECT * FROM gen
option (maxrecursion 10000)
...
Python recursive folder read
...tory may change during script execution, it's recommended to
# immediately convert program arguments to an absolute path. Then the variable root below will
# be an absolute path as well. Example:
# walk_dir = os.path.abspath(walk_dir)
print('walk_dir (absolute) = ' + os.path.abspath(walk_dir))
for ...
How can I shuffle the lines of a text file on the Unix command line or in a shell script?
...f. On some systems at least (doesn't appear to be in POSIX).
As jleedev pointed out: sort -R might also be an option. On some systems at least; well, you get the picture. It has been pointed out that sort -R doesn't really shuffle but instead sort items according to their hash value.
[Editor's not...
C++ Best way to get integer division and remainder
I am just wondering, if I want to divide a by b, and am interested both in the result c and the remainder (e.g. say I have number of seconds and want to split that into minutes and seconds), what is the best way to go about it?
...