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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?
...y optimization. rfind's behavior by definition is to only look at a single index when given pos=0, hence it is always an efficient check. Which syntax is more pleasant is a matter of preference.
– Yuval
Sep 11 at 0:26
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How to print out more than 20 items (documents) in MongoDB's shell?
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From the shell if you want to show all results you could do db.collection.find().toArray() to get all results without it.
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PostgreSQL DISTINCT ON with different ORDER BY
...t DESC;
If purchased_at can be NULL, use DESC NULLS LAST - and match your index for best performance. See:
Sort by column ASC, but NULL values first?
Why does ORDER BY NULLS LAST affect the query plan on a primary key?
Related, with more explanation:
Select first row in each GROUP BY group?
Sort...
Pass a data.frame column name to a function
...u need to either pass the column name quoted as a character or the integer index for the column. Just passing B will assume that B is an object itself.
– Shane
Apr 14 '10 at 23:14
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Multiple aggregations of the same column using pandas GroupBy.agg()
... functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
3 Answers
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How to update a menu item shown in the ActionBar?
...e-writing the desire text worked without problems:
if (mnuTopMenuActionBar_ != null) {
MenuItem mnuPageIndex = mnuTopMenuActionBar_
.findItem(R.id.menu_magazin_pageOfPage_text);
if (mnuPageIndex != null) {
if (getScreenOrientation() == 1) {
mnuPageIndex.setTitle...
Random “Element is no longer attached to the DOM” StaleElementReferenceException
...r valid. It's close to impossible for WebDriver to make a good guess about all the cases where this might happen - so it throws up its hands and gives control to you, who as the test/app author should know exactly what may or may not happen. What you want to do is explicitly wait until the DOM is in...
How to get RGB values from UIColor?
...rView.backgroundColor;//line 2
CGColorRef colorRef = [color CGColor];
int _countComponents = CGColorGetNumberOfComponents(colorRef);
if (_countComponents == 4) {
const CGFloat *_components = CGColorGetComponents(colorRef);
CGFloat red = _components[0];
CGFloat green = _components[1...
Min/Max-value validators in asp.net mvc
...MaxValueAttribute : ValidationAttribute
{
private readonly int _maxValue;
public MaxValueAttribute(int maxValue)
{
_maxValue = maxValue;
}
public override bool IsValid(object value)
{
return (int) value <= _maxValue;
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Zip lists in Python
...x. list, string, tuple, dictionary)
Output (list)
1st tuple = (element_1 of numbers, element_1 of letters)
2nd tuple = (e_2 numbers, e_2 letters)
…
n-th tuple = (e_n numbers, e_n letters)
List of n tuples: n is the length of the shortest argument (input)
len(numbers) =...