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Count the number occurrences of a character in a string
...)
Return the number of non-overlapping occurrences of substring sub in the range [start, end]. Optional arguments start and end are interpreted as in slice notation.
>>> sentence = 'Mary had a little lamb'
>>> sentence.count('a')
4
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Initialising an array of fixed size in python [duplicate]
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Do this:
>>> d = [ [ None for y in range( 2 ) ] for x in range( 2 ) ]
>>> d
[[None, None], [None, None]]
>>> d[0][0] = 1
>>> d
[[1, None], [None, None]]
The other solutions will lead to this kind of problem:
>>> d = [ [ N...
How to install a previous exact version of a NPM package?
...ion, an exact version will be installed. If you specify a semantic version range, then you might get a non-exact match. There's nothing unique about the install command in that respect.
– Bret Copeland
Jun 20 '15 at 18:49
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NSPredicate: filtering objects by day of NSDate property
... NSDate is a date-and-time -- you might want to use a midnight-to-midnight range.
– jlstrecker
Oct 17 '11 at 15:45
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Skip first entry in for loop in python?
...will run through the iterator. Try doing something like collections.deque(xrange(10000000)). There's no need to store all the ints in memory if you want to skip the first item...
– Roee Shenberg
Dec 4 '12 at 11:04
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Is it correct to use JavaScript Array.sort() method for shuffling?
...perfect" distribution if rand(x) is guaranteed to be exactly even over its range. Given that there are usually 2^x possible states for the RNG for some x, I don't think it'll be exactly even for rand(3).
– Jon Skeet
Jun 8 '09 at 5:28
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Selecting a row of pandas series/dataframe by integer index
...imagine this scenario
In [1]: df = pd.DataFrame(np.random.rand(5,2),index=range(0,10,2),columns=list('AB'))
In [2]: df
Out[2]:
A B
0 1.068932 -0.794307
2 -0.470056 1.192211
4 -0.284561 0.756029
6 1.037563 -0.267820
8 -0.538478 -0.800654
In [5]: df.iloc[[2]]
Out[5]:
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Check if a string contains a number
... @confused00 Nope, \d will match only a single digit in the range 0 to 9.
– thefourtheye
Nov 26 '16 at 5:12
10
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How to check if PHP array is associative or sequential?
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{
if (array() === $arr) return false;
return array_keys($arr) !== range(0, count($arr) - 1);
}
var_dump(isAssoc(['a', 'b', 'c'])); // false
var_dump(isAssoc(["0" => 'a', "1" => 'b', "2" => 'c'])); // false
var_dump(isAssoc(["1" => 'a', "0" => 'b', "2" => 'c'])); // true
v...
Declaring array of objects
... the trick or not? something like, i mean you don't need to know the index range if you just read it..
var arrayContainingObjects = [];
for (var i = 0; i < arrayContainingYourItems.length; i++){
arrayContainingObjects.push {(property: arrayContainingYourItems[i])};
}
Maybe i didn't underst...