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How to customize the background/border colors of a grouped table view cell?
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100
UPDATE: In iPhone OS 3.0 and later UITableViewCell now has a backgroundColor property that make...
Crontab Day of the Week syntax
In crontab does the Day of the Week field run from 0 - 6 or 1 -7 ?
3 Answers
3
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Minimizing NExpectation for a custom distribution in Mathematica
...f we plot pdf2 it looks exactly as your Plot
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x], {x, 0, .3}]
Now to the expected value. If I understand it correctly we have to integrate x * pdf[x] from -inf to +inf for a normal expected value.
x * pdf[x] looks like
Plot[pdf2[3.77, 1.34, -2.65, 0.40, x]*x...
Standard deviation of a list
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Since Python 3.4 / PEP450 there is a statistics module in the standard library, which has a method stdev for calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statis...
How to enumerate an enum with String type?
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Swift 4.2+
Starting with Swift 4.2 (with Xcode 10), just add protocol conformance to CaseIterable to benefit from allCases. To add this protocol conformance, you simply need to write somewhere:
extension Suit: CaseIterable {}
If the enum is your own, you may specify the c...
Reset keys of array elements in php?
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edited Jun 7 '18 at 19:04
Riz-waan
54322 silver badges1212 bronze badges
answered May 8 '12 at 5:09
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Pandas get topmost n records within each group
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>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...
In-memory size of a Python structure
...gt;>> import decimal
>>>
>>> d = {
... "int": 0,
... "float": 0.0,
... "dict": dict(),
... "set": set(),
... "tuple": tuple(),
... "list": list(),
... "str": "a",
... "unicode": u"a",
... "decimal": decimal.Decimal(0),
... "object": ob...
What is the “-->” operator in C++?
...ised that the following snippet compiled and worked in both Visual Studio 2008 and G++ 4.4.
25 Answers
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memory_get_peak_usage() with “real usage”
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+400
Ok, lets test this using a simple script:
ini_set('memory_limit', '1M');
$x = '';
while(true) {
echo "not real: ".(memory_get_peak...