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SQL query to get all values a enum can have
...
If you want an array:
SELECT enum_range(NULL::myenum)
If you want a separate record for each item in the enum:
SELECT unnest(enum_range(NULL::myenum))
Additional Information
This solution works as expected even if your enum is not in the default sch...
Zip lists in Python
...ts. Each element is a three-tuple.
See for yourself:
In [1]: a = b = c = range(20)
In [2]: zip(a, b, c)
Out[2]:
[(0, 0, 0),
(1, 1, 1),
...
(17, 17, 17),
(18, 18, 18),
(19, 19, 19)]
To find out how many elements each tuple contains, you could examine the length of the first element:
In [3...
Nested classes' scope?
...ll
fail:
class A:
a = 42
b = list(a + i for i in range(10))
http://docs.python.org/reference/executionmodel.html#naming-and-binding
The above means:
a function body is a code block and a method is a function, then names defined out of the function body present in a...
What is the use of the ArraySegment class?
... Console.WriteLine(segment.Count);
// Write the elements in the range specified in the ArraySegment.
Console.WriteLine("-- Range --");
for (int i = segment.Offset; i < segment.Count+segment.Offset; i++)
{
Console.WriteLine(segment.Array[i]);
...
What is the best data type to use for money in C#?
... floating-point types, the decimal type has more precision and a
smaller range, which makes it appropriate for financial and monetary
calculations.
You can use a decimal as follows:
decimal myMoney = 300.5m;
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...
Concatenating two lists - difference between '+=' and extend()
...ng code a few times (for Python 3):
import time
def test():
x = list(range(10000000))
y = list(range(10000000))
z = list(range(10000000))
# INPLACE_ADD
t0 = time.process_time()
z += x
t_inplace_add = time.process_time() - t0
# ADD
t0 = time.process_time()
...
Double Iteration in List Comprehension
... iterators may seem counter-intuitive.
Take for example: [str(x) for i in range(3) for x in foo(i)]
Let's decompose it:
def foo(i):
return i, i + 0.5
[str(x)
for i in range(3)
for x in foo(i)
]
# is same as
for i in range(3):
for x in foo(i):
yield str(x)
...
When should I use the “strictfp” keyword in java?
...
leeway is granted for an
implementation to use an extended
exponent range to represent
intermediate results; the net effect,
roughly speaking, is that a
calculation might produce "the correct
answer" in situations where exclusive
use of the float value set or double
value set migh...
How can I detect if a file is binary (non-text) in python?
...1) behavior:
>>> textchars = bytearray({7,8,9,10,12,13,27} | set(range(0x20, 0x100)) - {0x7f})
>>> is_binary_string = lambda bytes: bool(bytes.translate(None, textchars))
Example:
>>> is_binary_string(open('/usr/bin/python', 'rb').read(1024))
True
>>> is_binar...
How can I cast int to enum?
...
Just cast it:
MyEnum e = (MyEnum)3;
You can check if it's in range using Enum.IsDefined:
if (Enum.IsDefined(typeof(MyEnum), 3)) { ... }
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