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How to append rows to an R data frame
..., 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:n){
df$x[i...
PHP 安装 ZIP 扩展 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...、安装libzipcd usr local srcwget https: libzip org download libzip-1 3 2 tar gztar zxf libzip-1 3 2 tar gzcd libzip-1 3 2 configuremake && make install如 一、安装libzip
cd /usr/local/src
wget https://libzip.org/download/libzip-1.3.2.tar.gz
tar zxf libzip-1.3.2.tar.gz
cd libzip-1....
How to get the current time as datetime
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403
Update for Swift 3:
let date = Date()
let calendar = Calendar.current
let hour = calendar.compo...
What is the difference between 'content' and 'text'
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Nazim Kerimbekov
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answered Jun 9 '13 at 15:57
Gary KerrGary Ker...
Why does Python code run faster in a function?
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3 Answers
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$PHP_AUTOCONF errors on mac os x 10.7.3 when trying to install pecl extensions
...memcache and in both cases, I get similar errors. This is on MAC OS X 10.7.3 (lion) and I also have XCODE installed on it. I also installed Zend Server community edition before running these commands and have CFLAGS='-arch i386 -arch x86_64' environment variables set. So please help with what I need...
How do I clone a generic list in C#?
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398
You can use an extension method.
static class Extensions
{
public static IList<T> C...
How do I convert a String to an InputStream in Java?
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1433
Like this:
InputStream stream = new ByteArrayInputStream(exampleString.getBytes(StandardCharse...
SQL query to find record with ID not in another table
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edited Aug 21 '12 at 5:23
John Woo
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answer...