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How to append rows to an R data frame
... those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <- function(n){
df <- data.frame(x = numeric(n), y = character(n), stringsAsFactors = FALSE)
for(i in 1:...
Efficiency of purely functional programming
...trict evaluation semantics, not lazy) to one that can mutate data, an algorithm written for the impure Lisp that runs in O(n) can be translated to an algorithm in the pure Lisp that runs in O(n log n) time (based on work by Ben-Amram and Galil [1992] about simulating random access memory using only ...
Why do all browsers' user agents start with “Mozilla/”?
All popular browsers' user agent strings, even Internet Explorer's, start with Mozilla/ . Why is this the case?
6 Answers
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Directory does not exist. Parameter name: directoryVirtualPath
...same problem and found out that I had some bundles that pointed to non-exisiting files using {version} and * wildcards such as
bundles.Add(new ScriptBundle("~/bundles/jquery").Include(
"~/Scripts/jquery-{version}.js"));
I removed all of those and the error went away.
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Re-open *scratch* buffer in Emacs?
...cs default bindings:
C-xb *scratch* RET
or, more verbosely
M-x switch-to-buffer *scratch* RET
The *scratch* buffer is the buffer selected upon startup, and has the major mode Lisp Interaction. Note: the mode for the *scratch* buffer is controlled by the variable initial-major-mode.
In ...
The application was unable to start correctly (0xc000007b)
... have a client/server app which I have been developing on a single PC. Now it needs two serial ports, so I borrowed a PC from a friend.
...
Chrome refuses to execute an AJAX script due to wrong MIME type
...on Safari and other browsers but unfortunately will not execute in Chrome. It's coming with the following error:
7 Answers
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When should I use double or single quotes in JavaScript?
... and/or API consistency. Other than being consistent, use whichever best suits the string.
Using the other type of quote as a literal:
alert('Say "Hello"');
alert("Say 'Hello'");
This can get complicated:
alert("It's \"game\" time.");
alert('It\'s "game" time.');
Another option, new in ECMAScript...
Adding an identity to an existing column
I need to change the primary key of a table to an identity column, and there's already a number of rows in table.
19 Answe...
Is string in array?
What would be the best way to look in a string[] to see if it contains a element. This was my first shot at it. But perhaps there is something that I am overlooking. The array size will be no larger than 200 elements.
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