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Java 8: performance of Streams vs Collections
I'm new to Java 8. I still don't know the API in depth, but I've made a small informal benchmark to compare the performance of the new Streams API vs the good old Collections.
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MySQL - length() vs char_length()
...() returns the length of the string measured in characters.
This is especially relevant for Unicode, in which most characters are encoded in two bytes. Or UTF-8, where the number of bytes varies. For example:
select length(_utf8 '€'), char_length(_utf8 '€')
--> 3, 1
As you can see the E...
Can mustache iterate a top-level array?
...he');
var view = {test: 'div content', multiple : ['foo', 'bar'], multiple_2 : ['hello', 'world']};
var template = '<div>{{test}}</div><ul>{{#multiple}}<li>{{.}}</li>{{/multiple}}</ul><ul>{{#multiple_2}}<li>{{.}}</li>{{/multiple_2}}</ul>';...
Renaming columns in pandas
...UMNS
Use the df.rename() function and refer the columns to be renamed. Not all the columns have to be renamed:
df = df.rename(columns={'oldName1': 'newName1', 'oldName2': 'newName2'})
# Or rename the existing DataFrame (rather than creating a copy)
df.rename(columns={'oldName1': 'newName1', 'oldNam...
How often does python flush to a file?
...t size.
A negative buffering means to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
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Resolving ambiguous overload on function pointer and std::function for a lambda using +
...in comp.lang.c++.moderated if a closure type could add a typedef for result_type and the other typedefs required to make them adaptable (for instance by std::not1). I was told that it could not because this was observable. I'll try to find the link.
– Cassio Neri
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How do I run Python code from Sublime Text 2?
... find out where your Break key is here: http://en.wikipedia.org/wiki/Break_key.
Note: CTRL + C will NOT work.
What to do when Ctrl + Break does not work:
Go to:
Preferences -> Key Bindings - User
and paste the line below:
{"keys": ["ctrl+shift+c"], "command": "exec", "args": {"k...
How to get the anchor from the URL using jQuery?
...xOf() and .substring(), like this:
var url = "www.aaa.com/task1/1.3.html#a_1";
var hash = url.substring(url.indexOf("#")+1);
You can give it a try here, if it may not have a # in it, do an if(url.indexOf("#") != -1) check like this:
var url = "www.aaa.com/task1/1.3.html#a_1", idx = url.indexOf("...
How do I globally configure RSpec to keep the '--color' and '--format specdoc' options turned on
...
One can also use a spec_helper.rb file in all projects. The file should include the following:
RSpec.configure do |config|
# Use color in STDOUT
config.color = true
# Use color not only in STDOUT but also in pagers and files
config.tty = true
# Use the s...
List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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