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How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
Bash function to find newest file matching pattern
... Your one liner is giving me right answer, but the "right" way is actually giving me the oldest file. Any idea why?
– NewNameStat
Apr 4 '19 at 21:59
|...
How to set data attributes in HTML elements
...date your data-attributes with some spread, use --
$('body').attr({ 'data-test': 'text' });
-- otherwise, $('body').attr('data-test', 'text'); will work just fine.
Another way you could accomplish this is using --
$.extend( $('body')[0].dataset, { datum: true } );
-- which restricts any attri...
python pandas remove duplicate columns
...he given example, the returned value would be [False,False,True].
Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True])
F...
How to delete an SMS from the inbox in Android programmatically?
... onReceive() method, before performing anything with your message, simply call abortBroadcast();
EDIT: As of KitKat, this doesn't work anymore apparently.
EDIT2: More info on how to do it on KitKat here:
Delete SMS from android on 4.4.4 (Affected rows = 0(Zero), after deleted)
...
Generating v5 UUID. What is name and namespace?
...id = NameToUUID(Namespace_URL, 'http://stackoverflow.com/questions/5515880/test-vectors-for-uuid-version-5-converting-hash-into-guid-algorithm');
Now back to your question
For version 3 and version 5 UUIDs the additional command line arguments namespace and name have to be given. The namespace is ...
What is in your .vimrc? [closed]
...n a
" search will center on the line it's found in.
map N Nzz
map n nzz
" Testing
set completeopt=longest,menuone,preview
inoremap <expr> <cr> pumvisible() ? "\<c-y>" : "\<c-g>u\<cr>"
inoremap <expr> <c-n> pumvisible() ? "\<lt>c-n>" : "\<lt>...
What characters are allowed in DOM IDs? [duplicate]
...
Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
...
Is there an equivalent for var_dump (PHP) in Javascript?
...erting 'undefined' to 'empty
// string', the length greater than zero test can be applied in all cases.
var_name = typeof var_name === 'undefined' ? '':var_name;
var out = '';
var v_name = '';
switch (typeof var_value)
{
case "boolean":
v_name = var_name....