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Is there an easy way to create ordinals in C#?

...ly that hard to write a function to do it. public static string AddOrdinal(int num) { if( num <= 0 ) return num.ToString(); switch(num % 100) { case 11: case 12: case 13: return num + "th"; } switch(num % 10) { case 1: ...
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Confused about __str__ on list in Python [duplicate]

... Python has two different ways to convert an object to a string: str() and repr(). Printing an object uses str(); printing a list containing an object uses str() for the list itself, but the implementation of list.__str__() calls repr() for the individual it...
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How to use a variable to specify column name in ggplot

...t will remain around for a long time). The idiomatic way now would be to convert to a symbol the string that the variable contains, using sym()(which is almost the same as base aliases as.name() / as.symbol()), and unquote it using !! Simulating OP's data we can do : library(tidyverse) rates.by....
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Size of Matrix OpenCV

... cv:Mat mat; int rows = mat.rows; int cols = mat.cols; cv::Size s = mat.size(); rows = s.height; cols = s.width; Also note that stride >= cols; this means that actual size of the row can be greater than element size x cols. This is ...
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What does the thread_local mean in C++11?

...o data that is seemingly global or static storage duration (from the viewpoint of the functions using it) but in actual fact, there is one copy per thread. It adds to the current automatic (exists during a block/function), static (exists for the program duration) and dynamic (exists on the heap bet...
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How to check Google Play services version?

... I found simple solution: int v = getPackageManager().getPackageInfo(GoogleApiAvailability.GOOGLE_PLAY_SERVICES_PACKAGE, 0 ).versionCode; But versionCode is deprecated in API 28, so you can use PackageInfoCompat: long v = PackageInfoCompat.getLongV...
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Why NSUserDefaults failed to save NSMutableDictionary in iOS?

... When I need the data, I read out the NSData, and use NSKeyedUnarchiver to convert NSData back to the object. It is a little cumbersome, because i need to convert to/from NSData everytime, but it just works. Here is one example per request: Save: NSUserDefaults *defaults = [NSUserDefaults stand...
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Regex Named Groups in Java

... groups ( http://www.regular-expressions.info/named.html ) so can anyone point me towards a third-party library that does? ...
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Java Reflection: How to get the name of a variable?

..., here's an alternative (which I wouldn't use - see below): public void printFieldNames(Object obj, Foo... foos) { List<Foo> fooList = Arrays.asList(foos); for(Field field : obj.getClass().getFields()) { if(fooList.contains(field.get()) { System.out.println(fiel...
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Why use prefixes on member variables in C++ classes

...e for most of the "bad rap" that prefixes get. This notation is largely pointless in strongly typed languages e.g. in C++ "lpsz" to tell you that your string is a long pointer to a nul terminated string, when: segmented architecture is ancient history, C++ strings are by common convention pointers ...