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How can I split and parse a string in Python?
I am trying to split this string in python: 2.7.0_bf4fda703454
3 Answers
3
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What's the difference between “groups” and “captures” in .NET regular expressions?
...ew value. Not .NET, which will keep this history and places it in Captures[0].
If we change your regex to look as follows:
MatchCollection matches = Regex.Matches("{Q}{R}{S}", @"(\{[A-Z]\})+");
you will notice that the first Group will have one Captures (the first group always being the whole m...
Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...le(a = c(1, 2), b = c(11, 12))
newDT <- DT
.Internal(inspect(DT))
# @0000000003B7E2A0 19 VECSXP g0c7 [OBJ,NAM(2),ATT] (len=2, tl=100)
# @00000000040C2288 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 1,2
# @00000000040C2250 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 11,12
# ATTRIB: # ..snip..
.Inte...
How can I implode an array while skipping empty array items?
...ode('-', array_filter($array));
Obviously this will not work if you have 0 (or any other value that evaluates to false) in your array and you want to keep it. But then you can provide your own callback function.
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How do I make a transparent canvas in html5?
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edited Apr 16 '14 at 1:20
Lee Taylor
5,93777 gold badges2626 silver badges4343 bronze badges
answered ...
Logic to test that 3 of 4 are True
... (§4.7/4) indicates that converting bool to int gives the expected values 0 or 1.
In Java and C#, you can use the following construct:
if ((a?1:0) + (b?1:0) + (c?1:0) + (d?1:0) == 3)
...
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How do I draw a shadow under a UIView?
...eeds to happen after
CGContextSetShadow(currentContext, CGSizeMake(-15, 20), 5);
but before
CGContextRestoreGState(currentContext);
So if you want the superclass's drawRect: to be 'wrapped' in a shadow, then how about if you rearrange your code like this?
- (void)drawRect:(CGRect)rect {
...
Convert a number range to another range, maintaining ratio
...) + NewMin
Or if you want to protect for the case where the old range is 0 (OldMin = OldMax):
OldRange = (OldMax - OldMin)
if (OldRange == 0)
NewValue = NewMin
else
{
NewRange = (NewMax - NewMin)
NewValue = (((OldValue - OldMin) * NewRange) / OldRange) + NewMin
}
Note that in this...
Splitting a list into N parts of approximately equal length
...ken due to rounding errors. Do not use it!!!
assert len(chunkIt([1,2,3], 10)) == 10 # fails
Here's one that could work:
def chunkIt(seq, num):
avg = len(seq) / float(num)
out = []
last = 0.0
while last < len(seq):
out.append(seq[int(last):int(last + avg)])
...
Swift - How to convert String to Double
...e: The NSString doubleValue property is not recommended because it returns 0 if the value cannot be converted (i.e.: bad user input).
let lessPrecisePI = Float("3.14")
let morePrecisePI = Double("3.1415926536")
let invalidNumber = Float("alphabet") // nil, not a valid number
Unwrap the values to...