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How do I convert a double into a string in C++?

... The boost (tm) way: std::string str = boost::lexical_cast<std::string>(dbl); The Standard C++ way: std::ostringstream strs; strs << dbl; std::string str = strs.str(); Note: Don't forget #include <sstream> ...
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How do I rename all files to lowercase?

... user2066039: This must must be a recent thing on the Mac, because most answers older than a year don't account for it. I accomplished the task by using an intermediate extension like 'jpg1'. So, JPG -> jpg1 -> jpg. Hope that helps. – Joyce Nov 1 '...
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What's the fastest way to merge/join data.frames in R?

...bases as well. library(plyr) library(data.table) library(sqldf) set.seed(123) N <- 1e5 d1 <- data.frame(x=sample(N,N), y1=rnorm(N)) d2 <- data.frame(x=sample(N,N), y2=rnorm(N)) g1 <- sample(1:1000, N, replace = TRUE) g2<- sample(1:1000, N, replace = TRUE) d <- data.frame(d1, g1,...
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How do I make a Mac Terminal pop-up/alert? Applescript?

...ice, whatever that displays my custom text. How is this done? Also, is it possible to make one with several buttons that sets a variable? ...
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Why do I get “Pickle - EOFError: Ran out of input” reading an empty file?

... I would check that the file is not empty first: import os scores = {} # scores is an empty dict already if os.path.getsize(target) > 0: with open(target, "rb") as f: unpickler = pickle.Unpickler(f) # if file is not empty scores will be equal ...
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std::string to float or double

...to convert a string to a double. You can do it with the stringstream or boost::lexical_cast but those come with a performance penalty. Ahaha you have a Qt project ... QString winOpacity("0.6"); double temp = winOpacity.toDouble(); Extra note: If the input data is a const char*, QByteArray::to...
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onSaveInstanceState () and onRestoreInstanceState ()

... Usually you restore your state in onCreate(). It is possible to restore it in onRestoreInstanceState() as well, but not very common. (onRestoreInstanceState() is called after onStart(), whereas onCreate() is called before onStart(). Use the put methods to store values in onSav...
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Perl build, unit testing, code coverage: A complete working example

...tTestCall3, "false", "argumentTest() IS false test"); # Test argumentTest(123) my $argumentTestCall4 = HelloPerlBuildWorld::argumentTest(123); is($argumentTestCall4, "unknown", "argumentTest() IS unknown test"); Now back up in your top level project directory, create a text file named "Build.PL"...
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App Inventor 2 连接方式:AI伴侣、模拟器、USB · App Inventor 2 中文网

... 隐私策略和使用条款 技术支持 service@fun123.cn
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Go install fails with error: no install location for directory xxx outside GOPATH

... @RobertReiz while I share your frustration, I should point out that most other languages do in fact use these, but maybe they're not as visible. For example, Python (a language famous for its simplicity) has PYTHONHOME instead of GOROOT and PYTHONPATH instead of GOPATH. Even (GC)C has LIBRARY_...