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What is a regular expression for a MAC Address?
...is not valid in most flavors, except for BRE/ERE, which supports character range collation. However, support for character range collation varies among implementation, so the result may vary.
– nhahtdh
May 6 '15 at 3:14
...
How to print a string in fixed width?
... your combinations in one line with:
>>> [''.join(perm) for i in range(1, len(s)) for perm in it.permutations(s, i)]
['a', 'b', 'c', 'd', 'ab', 'ac', 'ad', 'ba', 'bc', 'bd', 'ca', 'cb', 'cd', 'da', 'db', 'dc', 'abc', 'abd', 'acb', 'acd', 'adb', 'adc', 'bac', 'bad', 'bca', 'bcd', 'bda', 'bd...
What does `unsigned` in MySQL mean and when to use it?
...onnegative numbers in a column
or when you need a larger upper
numeric range for the column. For
example, if an INT column is UNSIGNED,
the size of the column's range is the
same but its endpoints shift from
-2147483648 and 2147483647 up to 0 and 4294967295.
When do I use it ?
Ask yo...
how to listen to N channels? (dynamic select statement)
...g like this:
cases := make([]reflect.SelectCase, len(chans))
for i, ch := range chans {
cases[i] = reflect.SelectCase{Dir: reflect.SelectRecv, Chan: reflect.ValueOf(ch)}
}
chosen, value, ok := reflect.Select(cases)
// ok will be true if the channel has not been closed.
ch := chans[chosen]
msg :...
Plotting time in Python with Matplotlib
...e data
x = [datetime.datetime.now() + datetime.timedelta(hours=i) for i in range(12)]
y = [i+random.gauss(0,1) for i,_ in enumerate(x)]
# plot
plt.plot(x,y)
# beautify the x-labels
plt.gcf().autofmt_xdate()
plt.show()
Resulting image:
Here's the same as a scatter plot:
import datetime
impo...
Is the list of Python reserved words and builtins available in a library?
...xt', 'object', 'oct', 'open', 'ord', 'pow',
'print', 'property', 'quit', 'range', 'repr', 'reversed', 'round', 'set',
'setattr', 'slice', 'sorted', 'staticmethod', 'str', 'sum', 'super', 'tuple',
'type', 'vars', 'zip']
For Python 2 you'll need to use the __builtin__ module
>>> import ...
Getting a slice of keys from a map
...= make(map[int]string)
keys := make([]int, 0, len(mymap))
for k := range mymap {
keys = append(keys, k)
}
}
To be efficient in Go, it's important to minimize memory allocations.
share
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...
Is the LIKE operator case-sensitive with MSSQL Server?
...
It seems the range of characters like [A-Z] is always case-insensitive. [ABCDEFGHIJKLMNOPQRSŠTUVWXYZŽÅÄÖ] however seems to obey collation.
– jumxozizi
Oct 31 '16 at 15:49
...
Python nested functions variable scoping [duplicate]
... before assignment
This problem is caused by this line:
_total += PRICE_RANGES[key][0]
The documentation about Scopes and Namespaces says this:
A special quirk of Python is that – if no global statement is in effect – assignments to names always go into the innermost scope. Assignments...
Getting the index of the returned max or min item using max()/min() on a list
...mgetter() presented in the other answers, and use instead
index_min = min(range(len(values)), key=values.__getitem__)
because it doesn't require to import operator nor to use enumerate, and it is always faster(benchmark below) than a solution using itemgetter().
If you are dealing with numpy arr...