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Distinct() with lambda?
...your C# lambda expression into the native context of X. That is, LinqToSql converts your C# into SQL and executes that command natively wherever possible. This means any method that resides in C# can't be "passed through" a linqProvider if there's no way to express it in SQL (or whatever linq provi...
Getting a map() to return a list in Python 3.x
... going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
print(ch)
sh...
String, StringBuffer, and StringBuilder
... logic operations is rather slow, and is not advised at all, since the JVM converts the String to a StringBuffer in the bytecode. A lot of overhead is wasted converting from String to StringBuffer and then back to String again.
– Pieter van Niekerk
Jun 4 '10 at...
How do I convert a pandas Series or index to a Numpy array? [duplicate]
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I converted the pandas dataframe to list and then used the basic list.index(). Something like this:
dd = list(zone[0]) #Where zone[0] is some specific column of the table
idx = dd.index(filename[i])
You have you index value ...
How to execute XPath one-liners from shell?
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One package that is very likely to be installed on a system already is python-lxml. If so, this is possible without installing any extra package:
python -c "from lxml.etree import parse; from sys import stdin; print '\n'.join(parse(stdin).xpath('//element/@attribute'))"
...
Safely casting long to int in Java
...Ints.checkedCast(long) and Ints.saturatedCast(long) to get the nearest for converting long to int.
– Osify
Jun 17 '15 at 3:55
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How to convert SQL Query result to PANDAS Data Structure?
...RM rather than the expression language, you might find yourself wanting to convert an object of type sqlalchemy.orm.query.Query to a Pandas data frame.
The cleanest approach is to get the generated SQL from the query's statement attribute, and then execute it with pandas's read_sql() method. E.g.,...
IEnumerable vs List - What to Use? How do they work?
...once. But is it better overall? Well in the above, Leopards and Hyenas get converted into single SQL queries each, and the database only returns the rows that are relevant. But if we had returned a List from AllSpotted(), then it may run slower because the database could return far more data than is...
Set default CRAN mirror permanent in R
... it exists (which it does not in a 'factory-fresh' installation).
So do Sys.getenv("R_PROFILE") for the first option, or Sys.getenv("R_HOME") or R.home() for the second option. On macOS, the location of the second is /Library/Frameworks/R.framework/Resources/etc/.
The file may not exist, or you ...
ASP.NET MVC Html.DropDownList SelectedValue
...the view model to a SelectListItem, though you do have to implement a type converter as per Kazi's blog and register it to force the binder to treat this as a simple type.
In your controller we then have...
public ArticleController
{
...
public ActionResult Edit(int id)
{
...