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R object identification
...class)
sapply(obj, attributes)
attributes(obj)
names(obj)
as appropriate based on what's revealed. For example, try with:
obj <- data.frame(a=1:26, b=letters)
obj <- list(a=1:26, b=letters, c=list(d=1:26, e=letters))
data(cars)
obj <- lm(dist ~ speed, data=cars)
..etc.
If obj is an S...
What Haskell representation is recommended for 2D, unboxed pixel arrays with millions of pixels?
...nstance for Bool which does do bit packing, instead using a representation based on Word8. Howver, it is easy to write a bit-packing implementation for vectors -- here is one, from the (obsolete) uvector library. Under the hood, Repa uses Vectors, so I think it inherits that libraries representation...
Factory pattern in C#: How to ensure an object instance can only be created by a factory class?
... Any good way to require this architecture through an Interface/abstract base class? i.e. an interface/abstract base class that dictates that implementers should not expose a ctor.
– Arash Motamedi
Feb 19 '16 at 8:09
...
How can I ask the Selenium-WebDriver to wait for few seconds in Java?
...
That's import com.google.common.base.Function;, not import java.util.function.Function;
– haventchecked
Jun 22 '16 at 21:05
...
SELECT INTO using Oracle
...nto new_table
select * from old_table
/
If you want to create NEW_TABLE based on the records in OLD_TABLE ...
create table new_table as
select * from old_table
/
If the purpose is to create a new but empty table then use a WHERE clause with a condition which can never be true:
create table ...
How can I calculate an md5 checksum of a directory?
...ually everything (minus xattrs and acls), but it will sync owner and group based on their ID, not on string representation. So if you synced to a different system that doesn't necessarily have the same users/groups, you should add the --numeric-owner flag to tar
tar will include the filename of the...
Why can't I use an alias in a DELETE statement?
...
Example of a use case where this is important; deleting based on contents of a second table where there are multiple columns involved (i.e. so in or not in wouldn't work: DELETE f from dbo.foods as f where not exists (select top 1 1 from animalDiets a where a.AnimalId = f.AnimalId...
How to specify an element after which to wrap in css flexbox? [duplicate]
...to the jsfiddle. Playing around with it, I think I prefer a non-percentage-based approach, since percentage-based prevents further reflow as you shrink the container more, though you could certainly add more specific breakpoints as it shrinks (when it should go to 33%, etc).
– ...
What is a clean, pythonic way to have multiple constructors in Python?
...w__.
This could be used if the type of initialization cannot be selected based on the type of the constructor argument, and the constructors do not share code.
Example:
class MyClass(set):
def __init__(self, filename):
self._value = load_from_file(filename)
@classmethod
de...
Size of font in CSS with slash
...
To quote the official documentation:
The syntax of this property is based on a traditional typographical shorthand notation to set multiple properties related to fonts.
As David M said in the comments, it mirrors the typesetting tradition of specifying typeface sizes as “x pt on y pt...