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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 can I add an item to a SelectList in ASP.net MVC
Basically I am looking to insert an item at the beginning of a SelectList with the default value of 0 and the Text Value of " -- Select One --"
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Multi-line regex support in Vim
...t of other differences between Vim and Perl regexes.
Instead you can use \_., which means "match any single character including newline". It's a bit shorter than what you have. See :h /\_..
/This\_.*text/
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Get last n lines of a file, similar to tail
... blocks.append(f.read(BLOCK_SIZE))
else:
# file too small, start from begining
f.seek(0,0)
# only read what was not read
blocks.append(f.read(block_end_byte))
lines_found = blocks[-1].count('\n')
lines_to_go -= lines_found
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HTML-encoding lost when attribute read from input field
...e){
// Create a in-memory element, set its inner text (which is automatically encoded)
// Then grab the encoded contents back out. The element never exists on the DOM.
return $('<textarea/>').text(value).html();
}
function htmlDecode(value){
return $('<textarea/>').html(value).t...
Will strlen be calculated multiple times if used in a loop condition?
...optimiser might be able to deduce that the value won't change, but I personally wouldn't rely on that.
I'd do something like
for (int i = 0, n = strlen(ss); i < n; ++i)
or possibly
for (int i = 0; ss[i]; ++i)
as long as the string isn't going to change length during the iteration. If it mi...
ASP.NET MVC: What is the purpose of @section? [closed]
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@section is for defining a content are override from a shared view. Basically, it is a way for you to adjust your shared view (similar to a Master Page in Web Forms).
You might find Scott Gu's write up on this very interesting.
Edit: Based on additional question clarification
The @RenderSection...
Django admin: How to display a field that is marked as editable=False' in the model?
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+1. Especially if you don't plan to edit the field at all in Admin.
– Manoj Govindan
Oct 19 '10 at 16:05
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Managing relationships in Laravel, adhering to the repository pattern
...kiest part of this setup, for me at least, is determing if Eloquent is actually helping or harming us. ORMs are a tricky subject, because while they help us greatly from a practical point of view, they also couple your "business logic entities" code with the code doing the data retrieval.
This sort...
Get last element of Stream/List in a one-liner
...e for the general case:
Stream<T> stream = ...; // sequential or parallel stream
Optional<T> last = stream.reduce((first, second) -> second);
This implementations works for all ordered streams (including streams created from Lists). For unordered streams it is for obvious reasons u...