大约有 40,000 项符合查询结果（耗时：0.0664秒） [XML]
Floating point vs integer calculations on modern hardware
...
From my experience, there are many, many variables to performance...especially between integer & floating point math. It varies strongly from processor to processor (even within the same family such as x86) because different processors have different "pipeline" lengths. Also, some operations ...
Test if string is a number in Ruby on Rails
...def is_number? string
true if Float(string) rescue false
end
And then call it like this:
my_string = '12.34'
is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper function, t...
Failed to execute 'btoa' on 'Window': The string to be encoded contains characters outside of the La
...
If you have UTF8, use this (actually works with SVG source), like:
btoa(unescape(encodeURIComponent(str)))
example:
var imgsrc = 'data:image/svg+xml;base64,' + btoa(unescape(encodeURIComponent(markup)));
var img = new Image(1, 1); // width, height va...
How can I visualize per-character differences in a unified diff file?
...ight space changes):
git diff --color-words='[^[:space:]]|([[:alnum:]]|UTF_8_GUARD)+'
In general:
git diff --color-words=<re>
where <re> is a regexp defining "words" for the purpose of identifying changes.
These are less noisy in that they color the changed "words", whereas using ...
Why declare unicode by string in python?
...cepted since is the most complete one :)
– Oscar Carballal
Jul 3 '10 at 4:38
2
The default source...
How to sort in mongoose?
...t:{
date_added: -1 //Sort by Date Added DESC
}
},
function(err,allNews){
socket.emit('news-load', allNews); // Do something with the array of 10 objects
})
share
|
improve this answ...
Is there a ceiling equivalent of // operator in Python?
...t shy of an order of magnitude faster than forcing the float division and calling ceil(), provided you care about the speed. Which you shouldn't, unless you've proven through usage that you need to.
>>> timeit.timeit("((5 - 1) // 4) + 1", number = 100000000)
1.7249219375662506
>>>...
How can jQuery deferred be used?
... // or may not have been retrieved using an
// XHR request.
});
Basically, if the value has already been requested once before it's returned immediately from the cache. Otherwise, an AJAX request fetches the data and adds it to the cache. The $.when/.then doesn't care about any of this; all ...
push_back vs emplace_back
...h_back(Type&& _Val).
But the real C++0x form of emplace_back is really useful: void emplace_back(Args&&...);
Instead of taking a value_type it takes a variadic list of arguments, so that means that you can now perfectly forward the arguments and construct directly an object into a ...
How to change the background color of the options menu?
...
After spending a considerable amount of time trying all the options, the only way I was able to get an app using AppCompat v7 to change the overflow menu background was using the itemBackground attribute:
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar"&...