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What are some better ways to avoid the do-while(0); hack in C++?
...is considered acceptable practice to isolate these decisions in a function and use returns instead of breaks. While all these checks correspond to the same level of abstraction as of the function, it is quite logical approach.
For example:
void foo(...)
{
if (!condition)
{
return;
}...
To find whether a column exists in data frame or not
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Assuming that the name of your data frame is dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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undefined reference to `__android_log_print'
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Try the following in your Android.mk file:
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
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ios Upload Image and Text using HTTP POST
...forKey:[NSString stringWithString:@"title"]];
// the boundary string : a random string, that will not repeat in post data, to separate post data fields.
NSString *BoundaryConstant = [NSString stringWithString:@"----------V2ymHFg03ehbqgZCaKO6jy"];
// string constant for the post parameter 'file'. M...
How to remove a file from version control without deleting it?
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You want the --keep-local command-line option. This removes the file from version control without removing it from your filesystem.
$ svn rm --keep-local my_important_file
Note: The --keep-local only affects the svn rm of your copy. Other users may hav...
How do I use brew installed Python as the default Python?
I try to switch to Homebrew (after using fink and macport) on Mac OS X 10.6.2. I have installed python 2.7 with
19 Answers...
Convert javascript array to string
I'm trying to iterate over a "value" list and convert it into a string. Here is the code:
14 Answers
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How to check if string input is a number? [duplicate]
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Simply try converting it to an int and then bailing out if it doesn't work.
try:
val = int(userInput)
except ValueError:
print("That's not an int!")
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How do I create directory if none exists using File class in Ruby?
...tokens = dirname.split(/[\/\\]/) # don't forget the backslash for Windows! And to escape both "\" and "/"
1.upto(tokens.size) do |n|
dir = tokens[0...n]
Dir.mkdir(dir) unless Dir.exist?(dir)
end
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Big-O summary for Java Collections Framework implementations? [closed]
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And this is why we don't use URL's as answers. That document/server, as far as I can tell, is no longer available!
– Jason Mock
Apr 10 '13 at 16:01
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