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How can I get dictionary key as variable directly in Python (not by searching from value)?
...f you want to print key and value, use the following:
for key, value in my_dict.iteritems():
print key, value
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中文网（自研/维护）拓展 · App Inventor 2 中文网
...nt
Initialize(verticalArrangement)
Method for Initialize
Initialize_Scroll(verticalScrollArrangement)
Method for Initialize_Scroll
RemoveElement(elementIndex)
Method for RemoveElement
Set(list)
Method for Set
SetElement(elementIndex,element)
Method for SetElement
SetEleme...
How to delete a file via PHP?
...owing should help
realpath — Returns canonicalized absolute pathname
is_writable — Tells whether the filename is writable
unlink — Deletes a file
Run your filepath through realpath, then check if the returned path is writable and if so, unlink it.
...
What is the proper way to comment functions in Python?
...odule, function, class, or method definition. Such a docstring becomes the __doc__ special attribute of that object.
All modules should normally have docstrings, and all functions and classes exported by a module should also have docstrings. Public methods (including the __init__ constructor) s...
Calling constructors in c++ without new
...d the most common way of creating new dynamic objects instead of using auto_ptr, unique_ptr, or related.
– Fred Nurk
Jan 18 '11 at 13:18
3
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Python time measure function
... time2 = time.time()
print '%s function took %0.3f ms' % (f.func_name, (time2-time1)*1000.0)
return ret
return wrap
And the usage is very simple, just use the @timing decorator:
@timing
def do_work():
#code
Python 3:
def timing(f):
def wrap(*args, **kwargs):
ti...
Callback functions in C++
...ard algorithms library <algorithm> use callbacks. For example the for_each algorithm applies an unary callback to every item in a range of iterators:
template<class InputIt, class UnaryFunction>
UnaryFunction for_each(InputIt first, InputIt last, UnaryFunction f)
{
for (; first != las...
Count how many files in directory PHP
...
You can simply do the following :
$fi = new FilesystemIterator(__DIR__, FilesystemIterator::SKIP_DOTS);
printf("There were %d Files", iterator_count($fi));
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If table exists drop table then create it, if it does not exist just create it
...e and swap it with an old one (table contents are lost):
CREATE TABLE `bla__new` (id int); /* if not ok: terminate, report error */
RENAME TABLE `bla__new` to `bla`; /* if ok: terminate, report success */
RENAME TABLE `bla` to `bla__old`, `bla__new` to `bla`;
DROP TABLE IF EXISTS `bla__old`;
You...
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...