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std::enable_if to conditionally compile a member function
...rying to get a simple example to work to understand how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
...
Use numpy array in shared memory for multiprocessing
...not available anymore) and @Henry Gomersall's answers. You could use shared_arr.get_lock() to synchronize access when needed:
shared_arr = mp.Array(ctypes.c_double, N)
# ...
def f(i): # could be anything numpy accepts as an index such another numpy array
with shared_arr.get_lock(): # synchroniz...
What is the difference between a field and a property?
...It is private to your class and stores the actual data.
private string _myField;
// this is a property. When accessed it uses the underlying field,
// but only exposes the contract, which will not be affected by the underlying field
public string MyProperty
{
get
...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
...$dev/statistics";
my %stats = do {
opendir +(my $dh), $dir;
local @_ = readdir $dh;
closedir $dh;
map +($_, []), grep !/^\.\.?$/, @_;
};
if (-t STDOUT) {
while (1) {
print "\033[H\033[J", run();
my ($time, $us) = gettimeofday();
my ($sec, $min, $hour) = l...
Xcode 5.1 - No architectures to compile for (ONLY_ACTIVE_ARCH=YES, active arch=x86_64, VALID_ARCHS=i
...
What you need to do is just set the ONLY_ACTIVE_ARCH to NO (at least works for me). Below is a screenshot for it:
EDIT:
As far as I know (please point it out if there's something wrong, thanks), if you set ONLY_ACTIVE_ARCH to YES, it means the Xcode will only...
What optimizations can GHC be expected to perform reliably?
...1.0-6e4c9bdc36eeb9121f27ccbbcb62e3f3
wired-in package rts mapped to builtin_rts
wired-in package template-haskell mapped to template-haskell-2.7.0.0-2bd128e15c2d50997ec26a1eaf8b23bf
wired-in package dph-seq not found.
wired-in package dph-par not found.
Hsc static flags: -static
*** Chasing dependen...
What's the difference between django OneToOneField and ForeignKey?
...)
>>> e2 = Engine2.objects.get(name='Wankel')
>>> e2.car2_set.all()
[<Car2: Mazda>]
Model Code
from django.db import models
class Engine(models.Model):
name = models.CharField(max_length=25)
def __unicode__(self):
return self.name
class Car(models.Model)...
How to import a module given the full path?
...
For Python 3.5+ use:
import importlib.util
spec = importlib.util.spec_from_file_location("module.name", "/path/to/file.py")
foo = importlib.util.module_from_spec(spec)
spec.loader.exec_module(foo)
foo.MyClass()
For Python 3.3 and 3.4 use:
from importlib.machinery import SourceFileLoader
fo...
How do I get an object's unqualified (short) class name?
...Greg.Forbes Because Tenant doesn't exist in the current namespace. Try var_dump($tenant instanceof \Library\Entity\People\Tenant) instead. Also, investigate how to use the use operator, and the general concept behind PHP namespaces!
– lonesomeday
Nov 13 '13 at...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
...er.pal(5,"Set1")
names(myColors) <- levels(dat$grp)
colScale <- scale_colour_manual(name = "grp",values = myColors)
and then add the color scale onto the plot as needed:
#One plot with all the data
p <- ggplot(dat,aes(x,y,colour = grp)) + geom_point()
p1 <- p + colScale
#A second plo...