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How to get the position of a character in Python?
...ring.index('s')
2
>>> myString.index('x')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: substring not found
From the Python manual
string.find(s, sub[, start[, end]])
Return the lowest index in s where the substring sub is found s...
Get the Row(s) which have the max count in groups using groupby
How do I find all rows in a pandas dataframe which have the max value for count column, after grouping by ['Sp','Mt'] columns?
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Named placeholders in string formatting
...the file won't be loaded into memory.
– Edward Corrigall
Sep 20 '19 at 17:44
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Is it good practice to use the xor operator for boolean checks? [closed]
...like the exclusive or , ^ , operator when it makes sense in the context of boolean checks because of its conciseness. I much prefer to write
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php Replacing multiple spaces with a single space [duplicate]
...e: preg_replace('/(?:\s\s+|\n|\t)/', ' ', $x) will be more efficient especially on text with several single spaces ?
– codaddict
Mar 3 '10 at 4:23
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Entity Framework 6 Code first Default value
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You can do it by manually edit code first migration:
public override void Up()
{
AddColumn("dbo.Events", "Active", c => c.Boolean(nullable: false, defaultValue: true));
}
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Is the order of iterating through std::map known (and guaranteed by the standard)?
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Yes, that's guaranteed. Moreover, *begin() gives you the smallest and *rbegin() the largest element, as determined by the comparison operator, and two key values a and b for which the expression !compare(a,b) && !compare(b,a) is true are considered equal. The default comparis...
Copy a stream to avoid “stream has already been operated upon or closed”
...ata, then by definition you either have to generate it twice (deterministically) or store it. If it already happens to be in a collection, great; then iterating it twice is cheap.
We did experiment in the design with "forked streams". What we found was that supporting this had real costs; it bu...
ImportError: No module named Crypto.Cipher
...alenv keeps returning the error listed above. My import statement is just from Crypto.Cipher import AES . I looked for duplicates and you might say that there are some, but I tried the solutions (although most are not even solutions) and nothing worked.
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Remove empty elements from an array in Javascript
...ll return you a new array with the elements that pass the criteria of the callback function you provide to it.
For example, if you want to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
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