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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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How do you round to 1 decimal place in Javascript?
...turn Math.round(value * multiplier) / multiplier;
}
... usage ...
round(12345.6789, 2) // 12345.68
round(12345.6789, 1) // 12345.7
... defaults to round to nearest whole number (precision 0) ...
round(12345.6789) // 12346
... and can be used to round to nearest 10 or 100 etc...
round(12345....
Change the Right Margin of a View Programmatically?
...
Use This function to set all Type of margins
public void setViewMargins(Context con, ViewGroup.LayoutParams params,
int left, int top , int right, int bottom, View view) {
final float scale = con.getResources(...
Update multiple rows in same query using PostgreSQL
...izable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c = c.column_c
from (values
('12...
Extract digits from a string in Java
...cimal point, it removes the decimal point too. str = str.replaceAll("[^\\.0123456789]","");
– Aravindan R
Jan 10 '12 at 22:21
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How to map with index in Ruby?
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Here are two more options for 1.8.6 (or 1.9) without using enumerator:
# Fun with functional
arr = ('a'..'g').to_a
arr.zip( (2..(arr.length+2)).to_a )
#=> [["a", 2], ["b", 3], ["c", 4], ["d", 5], ["e", 6], ["f", 7], ["g", 8]]
# The simplest
n = 1
arr.map{ |c| [c, n+=1 ] }
#=> [["a", 2], ["b...
How to delete last character from a string using jQuery?
How to delete last character from a string for instance in 123-4- when I delete 4 it should display 123- using jQuery .
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How can I iterate over an enum?
...b = 220,
c = -1
};
static const Type All[] = { a, b, c };
}
void fun( const MyEnum::Type e )
{
std::cout << e << std::endl;
}
int main()
{
// all
for ( const auto e : MyEnum::All )
fun( e );
// some
for ( const auto e : { MyEnum::a, MyEnum::b } )
fun( e );
...
Python __str__ versus __unicode__
...by side with __str__.
class A :
def __init__(self) :
self.x = 123
self.y = 23.3
#def __str__(self) :
# return "STR {} {}".format( self.x , self.y)
def __unicode__(self) :
return u"UNICODE {} {}".format( self.x , self.y)
a1 = A()
a2 = A()
...
Best practices for API versioning? [closed]
... behave identically to all API requests):
http://shonzilla/api/customers/1234
http://shonzilla/api/v3.0/customers/1234
http://shonzilla/api/v3/customers/1234
In addition, API clients that still try to point to the old API should be informed to use the latest previous API version, if the API vers...