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What are the differences between “generic” types in C++ and Java?
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It's not purely syntactic sugar. The compiler uses this information for checking types. Even though the information isn't available at runt...
Remove all occurrences of char from string
...cher.quoteReplacement(replacement.toString()));
– Sal_Vader_808
Jun 27 '18 at 19:14
add a com...
https URL with token parameter : how secure is it?
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– Jason Punyon♦
Mar 13 '09 at 17:32
add a comment
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Determine the data types of a data frame's columns
...o use ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
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FirstOrDefault: Default value other than null
...3
RB.RB.
32.7k1010 gold badges7878 silver badges116116 bronze badges
a...
What is the purpose of the word 'self'?
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But in __init__(self) method, it accepts self, then even without creating the object, how does it refer to itself?
– saurav
Jan 28 '18 at 10:10
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记录一些Mac OS X技巧 - 更多技术 - 清泛网 - 专注C/C++及内核技术
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sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.dynamic_pager.plist
禁用以后，磁盘上还保留着这些交换文件，它们已经没用了，也可以删掉：
sudo rm /private/var/vm/swapfile*
如果要重新启用虚拟内存的话，可以执行这条命令：
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What is the difference between String.Empty and “” (empty string)?
...private hidebysig instance string foo() cil managed
{
.maxstack 8
L_0000: ldstr "foo"
L_0005: ret
}
.method private hidebysig instance string bar() cil managed
{
.maxstack 8
L_0000: ldstr "bar"
L_0005: ldsfld string [mscorlib]System.String::Empty
L_000a: call string [msc...
Prevent row names to be written to file when using write.csv
...te.csv(data, "baseR_file.csv", row.names = F) 13.8066424 13.8248250 13.9118324 13.8776993 13.9269675 14.3241311 10
## write_csv(data, "readr_file.csv") 3.6742610 3.7999409 3.8572456 3.8690681 3.8991995 4.0637453 10
## fwrite(data, "datatable_file.csv") 0.3...
Convert a string to an enum in C#
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KeithKeith
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