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How to get a variable value if variable name is stored as string?
...ariable_value="\$$variable_name"
fi
echo "$variable_value"
}
test=123
get_value_of test
# 123
test="\$(echo \"something nasty\")"
get_value_of test
# $(echo "something nasty")
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Grep characters before and after match?
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3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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How can I enable auto complete support in Notepad++?
...r found any more documentation, but cpp.xml has a calltip for fopen, while php.xml is quite complete.
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How to force R to use a specified factor level as reference in a regression?
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See the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor ...
Google Authenticator available as a public service?
...o not know if there is a specific implementation for your server software (PHP, Java, .NET, etc.)
But, specifically, you don't need an offsite service to handle this.
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What is boxing and unboxing and what are the trade offs?
...xing is the conversion of a reference type into a value type.
EX: int i = 123;
object o = i;// Boxing
int j = (int)o;// UnBoxing
Value Types are: int, char and structures, enumerations.
Reference Types are:
Classes,interfaces,arrays,strings and objects
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Array_merge versus + [duplicate]
... the matching elements from the right-hand array will be ignored.
http://php.net/manual/en/language.operators.array.php
array_merge() has slightly different behavior:
If the input arrays have the same string keys, then the later value for that key will overwrite the previous one. If, however,...
Fastest check if row exists in PostgreSQL
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How about simply:
select 1 from tbl where userid = 123 limit 1;
where 123 is the userid of the batch that you're about to insert.
The above query will return either an empty set or a single row, depending on whether there are records with the given userid.
If this turns o...
盘点微软历史上9大失败软件产品！ - 创意 - 清泛网 - 专注C/C++及内核技术
...面。希望满足初级计算机用户的需求，或许这个概念没有问题，但是过于简单，只是讲解如何使用计算机，售价却高达100美元，结果在没有市场的情况下被淘汰了。有趣的是，Bob项目是由盖茨的老婆梅林达负责管理的。
2、MSN Me...
智能手机图形解锁有多少种可能 - 创意 - 清泛网 - 专注C/C++及内核技术
智能手机图形解锁有多少种可能琢磨这个问题很久，今天还用matlab算了算，到后来才发现自己漏掉了一些情况，如下图中绿色的两幅，24136和654192都是可行的，也就是说：这...琢磨这个问题很久，今天还用matlab算了算，到后来才...