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How to rename a single column in a data.frame?
I know if I have a data frame with more than 1 column, I can use
20 Answers
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How can I get a web site's favicon?
...s/files from the same place. Getting the default icons from my system for known file types isn't terribly complicated, but I don't know how to get the favicon from a website. (SO has the grey->orange stack icon in the address bar for instance)
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Why are Oracle table/column/index names limited to 30 characters?
...understand that many years ago there would be this kind of limitation, but nowadays surely this limit could easily be increased. We have naming conventions for objects, but there is always a case that turns up where we hit this limit - especially in naming foreign keys.
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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...135 | 1135 | 1200 | 4357 | 1137 | 1188 | 4294 |
Findings
Nowadays, all evergreen browsers handle string concatenation well. Array.join only helps IE 11
Overall, Opera is fastest, 4 times as fast as Array.join
Firefox is second and Array.join is only slightly slower in FF but consi...
Hash collision in git
... hex character string... that's 4 bits per character times 40... 160 bits. Now we know 10 bits is approximately 1000 (1024 to be exact) meaning that there are 1 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 000 different SHA-1 hashes... 1048.
What is this equivalent of? Well the Moon i...
Cache an HTTP 'Get' service response in AngularJS?
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I think there's an even easier way now. This enables basic caching for all $http requests (which $resource inherits):
var app = angular.module('myApp',[])
.config(['$httpProvider', function ($httpProvider) {
// enable http caching
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custom listview adapter getView method being called multiple times, and in no coherent order
... ListView to measure a few children out of the adapter at layout time, to know how big it should be. This is what provides ListView with the convertViews you see passed to getView() even before you scroll.
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jquery's append not working with svg element?
...eading this answer I changed my createElement calls to createElementNS and now everything works!
– kitsu.eb
Jul 12 '13 at 21:01
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What is the documents directory (NSDocumentDirectory)?
...ch with @"~/Documents". Hardcoding paths is never a good idea. It may work now, but if Apple ever chooses to rename or move the Documents directory, your app will break. NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); will always give you the correct directory!
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How to use NSURLConnection to connect with SSL for an untrusted cert?
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These methods are now considered deprecated as of iOS 5.0 and Mac OS X 10.6. The -(void)connection:(NSURLConnection *)connection willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge method should be used instead....