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Group by multiple columns in dplyr, using string vector input
...ot the character versions of the names, but how you would refer to them in foo$bar; bar is not quoted here. Or how you'd refer to variables in a formula: foo ~ bar.
@Arun also mentions that you can do:
df %.%
group_by("asdfgfTgdsx", "asdfk30v0ja") %.%
summarise(Value = mean(value))
But y...
How can I force clients to refresh JavaScript files?
...ecified, as it simply looks at the full file name without interpreting it. foo.js?1 is not the same name as foo.js?2, so the browser will think they are two different files. One downside is that both files will simultaneously exist in the users' cache, taking up unnecessary space.
...
How to throw an exception in C?
...clude <stdint.h>
#include <cstdio>
extern "C" int bar1();
void foo()
{
try{
bar1();
}catch(int64_t x){
printf("good %ld",x);
}
}
int main(int argc, char *argv[])
{
foo();
return 0;
}
to compile it
gcc -o bar.o -c bar.c && g++ a.cc bar.o && ./a.out
o...
Will #if RELEASE work like #if DEBUG does in C#?
In all the examples I've seen of the #if compiler directive, they use "DEBUG". Can I use "RELEASE" in the same way to exclude code that I don't want to run when compiled in debug mode? The code I want to surround with this block sends out a bunch of emails, and I don't want to accidentally send tho...
Case insensitive string compare in LINQ-to-SQL
...ct.
For example this LINQ query:
from user in Users
where user.Email == "foo@bar.com"
select user
gets translated to the following SQL by the LINQ-to-SQL provider:
SELECT [t0].[Email]
FROM [User] AS [t0]
WHERE [t0].[Email] = @p0
-- note that "@p0" is defined as nvarchar(11)
-- and is passed my ...
Side-by-side plots with ggplot2
...ect to a file, specify a device driver (such as pdf, png, etc), e.g.
pdf("foo.pdf")
grid.arrange(plot1, plot2)
dev.off()
or, use arrangeGrob() in combination with ggsave(),
ggsave("foo.pdf", arrangeGrob(plot1, plot2))
This is the equivalent of making two distinct plots using par(mfrow = c(1,2)...
Create array of all integers between two numbers, inclusive, in Javascript/jQuery [duplicate]
Say I have the following checkbox:
15 Answers
15
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How to capitalize the first character of each word in a string
...
WordUtils.capitalize(str) (from apache commons-text)
(Note: if you need "fOO BAr" to become "Foo Bar", then use capitalizeFully(..) instead)
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Where is debug.keystore in Android Studio
I need to enable google+ api, so I need the debug.keystore . I switched to Android Studio and do not know where it is. I can find it in eclipse at path ~/.android/debug.keystore.
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