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Getting distance between two points based on latitude/longitude
...nit.MILES)
>> 243.71201856934454 # in miles
# you can also use the string abbreviation for units:
haversine(lyon, paris, unit='mi')
>> 243.71201856934454 # in miles
haversine(lyon, paris, unit=Unit.NAUTICAL_MILES)
>> 211.78037755311516 # in nautical miles
They claim to have ...
Usage of __slots__?
...Unifying types and classes in Python 2.2
If you subclass a built-in type, extra space is automatically added to the instances to accomodate __dict__ and __weakrefs__. (The __dict__ is not initialized until you use it though, so you shouldn't worry about the space occupied by an empty dictionary for...
Javascript callback when IFRAME is finished loading?
...cript">
function on_load(iframe) {
try {
// Displays the first 50 chars in the innerHTML of the
// body of the page that the iframe is showing.
// EDIT 2012-04-17: for wider support, fallback to contentWindow.document
var doc = iframe.contentDocument || iframe.contentWindow.docu...
google oauth2 redirect_uri with several parameters
...
state=THE_STATE_PARAMETERS
So for your case,do this:
/1. create a json string of your parameters ->
{ "a" : "b" , "c" : 1 }
/2. do a base64UrlEncode , to make it URL safe ->
stateString = base64UrlEncode('{ "a" : "b" , "c" : 1 }');
This is a PHP example of base64UrlEncoding & de...
What does the “__block” keyword mean?
...c NSInteger CounterStatic;
{
NSInteger localCounter = 42;
__block char localCharacter;
void (^aBlock)(void) = ^(void) {
++CounterGlobal;
++CounterStatic;
CounterGlobal = localCounter; // localCounter fixed at block creation
localCharacter = 'a'; // sets ...
Performance difference for control structures 'for' and 'foreach' in C#
...date. I did a small test, just to see. Here is the code:
static void Main(string[] args)
{
List<int> intList = new List<int>();
for (int i = 0; i < 10000000; i++)
{
intList.Add(i);
}
DateTime timeStarted = DateTime.Now;
for (int i = 0; i < intList...
Pimpl idiom vs Pure virtual class interface
... important. It's appropriate for it to be a key in a std::map. Example, a "string" class, or a "date" class, or a "complex number" class. To "copy" instances of such a class makes sense.
An Entity type
Identity is important. Always passed by reference, never by "value". Often, doesn't make sense t...
What makes a keychain item unique (in iOS)?
...ivate keys. That's a lot different to Apple's sample code that only stores string credentials (username/password). However, I have found out that when you set the kSecClass to kSecClassCertificate or kSecClassKey the Keychain checks also if the entry (the value) is already stored. This prevents from...
MySQL复制的概述、安装、故障、技巧、工具 - 数据库(内核) - 清泛网 - 专注...
...表可以使用不同的键类型。比如主服务器用InnoDB，键用VARCHAR的话节省空间，从服务器使用MyISAM，键用CHAR提高速度，因为MyISAM有静态表一说。
主从服务器中的表可以使用不同的索引。主服务器主要用来应付写操作，所以除了主...
Which is more efficient: Multiple MySQL tables or one large table?
...ow on top of a legacy system. I had to expand the old database tables with extra columns. I decided to make new tables for the new data. Some new features come in handy for the legacy system and now I can easily integrate them without having to rewrite too much of the old queries
...