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What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
...
This part is new. Expression Literals
When you have an expression (M_PI / 16 for example) you should put it inside parenthesis.
This syntax works for numeral expressions, booleans, finding an index in a (C-) string, boolean values, enum constants, and even character strings!
NSNumber *piO...
Proper way to declare custom exceptions in modern Python?
... (or pass extra args), do this:
class ValidationError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super(ValidationError, self).__init__(message)
# Now for your custom code...
self.errors = erro...
Easy pretty printing of floats in python?
...most exactly) this command you said you made up:
import numpy as np
np.set_printoptions(precision=2)
Or even better in your case if you still want to see all decimals of really precise numbers, but get rid of trailing zeros for example, use the formatting string %g:
np.set_printoptions(formatter...
How to sort an IEnumerable
...myList = myEnumerable.ToList();
myList.Sort();
Based on your comment:
_components = (from c in xml.Descendants("component")
let value = (string)c
orderby value
select value
)
.Distinct()
.ToList();
or
_com...
machine learning libraries in C# [closed]
...asses:
public class TrainingSet
{
private readonly List<string> _attributes = new List<string>();
private readonly List<List<object>> _examples = new List<List<object>>();
public TrainingSet(params string[] attributes)
{
_attributes.AddRang...
How to import the class within the same directory or sub directory?
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Python 2
Make an empty file called __init__.py in the same directory as the files. That will signify to Python that it's "ok to import from this directory".
Then just do...
from user import User
from dir import Dir
The same holds true if the files are in a...
Installing older version of R package
...ageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz"
install.packages(packageurl, repos=NULL, type="source")
If this doesn't work for you and you're on Windows, the reason is probably the lack of an appropriate tool chain for building/compiling packages. Normal...
Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?
...
FYI: g++ has __attribute__ syntax for selectively 'export' symbols: #define DLLEXPORT __attribute__ ((visibility("default"))) #define DLLLOCAL __attribute__ ((visibility("hidden")))
– Brian Cannard
...
How do I filter query objects by date range in Django?
...
Use
Sample.objects.filter(date__range=["2011-01-01", "2011-01-31"])
Or if you are just trying to filter month wise:
Sample.objects.filter(date__year='2011',
date__month='01')
Edit
As Bernhard Vallant said, if you want a query...
Return a value if no rows are found in Microsoft tSQL
... but ideally it should return multiple values. select case when count(QTIB_REQ_)<1 then 0 else QTIB_REQ_ end from qb_requisitions_all where QTIB_REQ_ IN ($Req_disabled_WA) and CLIENT___BENCH___NON_BILLABLE NOT IN ( 'Non Billable', 'Non-Billable', 'NonBillable', 'Bench', 'Bench - SC Cleared S...