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Remove rows with all or some NAs (missing values) in data.frame
...ata.frame does not support cols=.
Benchmark result
Here is a comparison of base (blue), dplyr (pink), and data.table (yellow) methods for dropping either all or select missing observations, on notional dataset of 1 million observations of 20 numeric variables with independent 5% likelihood of being ...
How can I have a newline in a string in sh?
...
What I did based on the other answers was
NEWLINE=$'\n'
my_var="__between eggs and bacon__"
echo "spam${NEWLINE}eggs${my_var}bacon${NEWLINE}knight"
# which outputs:
spam
eggs__between eggs and bacon__bacon
knight
...
How to loop through an array containing objects and access their properties
...sum / myArray.length;
console.log(average); // 200
5. Create a new array based on the original but without modifying it
const myArray = [{x:100}, {x:200}, {x:300}];
const newArray= myArray.map(element => {
return {
...element,
x: element.x * 2
};
});
console.log(myArr...
How to construct a timedelta object from a simple string
... format(5hr34m56s), you should parse using regular expressions
Here is re-based solution:
import re
from datetime import timedelta
regex = re.compile(r'((?P<hours>\d+?)hr)?((?P<minutes>\d+?)m)?((?P<seconds>\d+?)s)?')
def parse_time(time_str):
parts = regex.match(time_str)...
Get week of year in JavaScript like in PHP
...ter link on the same site is: Working with weeks.
Edit
Here is some code based on the links provided and that posted eariler by Dommer. It has been lightly tested against results at http://www.merlyn.demon.co.uk/js-date6.htm#YWD. Please test thoroughly, no guarantee provided.
Edit 2017
There was...
How to get a JavaScript object's class?
...etClass() in JavaScript. Mostly that's due to JavaScript being a prototype-based language, as opposed to Java being a class-based one.
Depending on what you need getClass() for, there are several options in JavaScript:
typeof
instanceof
obj.constructor
func.prototype, proto.isPrototypeOf
A few...
Why does C# allow {} code blocks without a preceding statement?
...You could say it all comes down to the fact that USA programme language (C based) design won rather than European programme language (Modula-2 based) design.
(Control statements act on a single statement, statements can be groups to create new statements)
...
Exception thrown in catch and finally clause
...
Based on reading your answer and seeing how you likely came up with it, I believe you think an "exception-in-progress" has "precedence". Keep in mind:
When an new exception is thrown in a catch block or finally block that w...
Converting XML to JSON using Python?
...ML to a dict+list+string structure, following this "standard". It is Expat-based, so it's very fast and doesn't need to load the whole XML tree in memory.
Once you have that data structure, you can serialize it to JSON:
import xmltodict, json
o = xmltodict.parse('<e> <a>text</a>...
How can I put a database under git (version control)?
...some major changes, the thing is, these changes require changes to the database schema, so I'd like to put the entire database under git as well.
...