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Creating an R dataframe row-by-row
...s to code in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
stringsAsFactors=FALSE) # you don't know lev...
JSON.net: how to deserialize without using the default constructor?
I have a class that has a default constructor and also an overloaded constructor that takes in a set of parameters. These parameters match to fields on the object and are assigned on construction. At this point i need the default constructor for other purposes so i would like to keep it if i can. ...
Razor comment syntax
...lighting won't work.
@{
//This is a comment
}
@{/*
This is a multi
line comment
*/}
@*
This is a comment, as well
*@
Is the updated method @//This is a comment and @/* */ will no longer work.
share...
How can I search (case-insensitive) in a column using LIKE wildcard?
...nition, you can just omit all these tricks: it will work automatically.
ALTER TABLE trees
MODIFY COLUMN title VARCHAR(…) CHARACTER
SET UTF8 COLLATE UTF8_GENERAL_CI.
This will also rebuild any indexes on this column so that they could be used for the queries without leading '%'
...
Have a div cling to top of screen if scrolled down past it [duplicate]
... var $window = $(window),
$stickyEl = $('#the-sticky-div'),
elTop = $stickyEl.offset().top;
$window.scroll(function() {
$stickyEl.toggleClass('sticky', $window.scrollTop() > elTop);
});
This simply adds a sticky CSS class when the page has scrolled past it, and rem...
Floating point vs integer calculations on modern hardware
...ion floating point arithmetic, as the same operation can be performed on multiple data at once, plus there is a separate* bank of registers for the SSE operations. (I noticed in your second example you used "float" instead of "double", making me think you are using single-precision math).
*Note: ...
php implode (101) with quotes
...
Thanks. I used this for <ul> <li> {!! implode('</li><li>', session('messages')) !!} </li> </ul>
– marlo
May 31 '17 at 5:02
...
Is there a way to make GHC provide the type class constraints of typed holes?
... 8.0 thanks to @DominiqueDevriese's GHC ticket.
Due to extended type defaulting, this isn't immediately obvious in GHCi. With your example,
> show _
<interactive>:7:6: error:
• Found hole: _h :: ()
Or perhaps ‘_h’ is mis-spelled, or not in scope
• In the first arg...
Alternative to itoa() for converting integer to string C++? [duplicate]
I was wondering if there was an alternative to itoa() for converting an integer to a string because when I run it in visual Studio I get warnings, and when I try to build my program under Linux, I get a compilation error.
...
What can I do to resolve a “Row not found or changed” Exception in LINQ to SQL on a SQL Server Compa
..." + GetChangeConflictExceptionDetailString(context))
{
}
/// <summary>
/// Code from following link
/// https://ittecture.wordpress.com/2008/10/17/tip-of-the-day-3/
/// </summary>
/// <param name="context"></param>
/// <returns></retu...