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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...re allowed (e.g. changing order of elements of each vector, changing order and names of variables, shortening variables, changing case of strings). From this, you should be able to figure out what was missing from one or the other. For example (this is not very elegant):
difference <-
data.fr...
How to print from GitHub
...ne of code in the URL field.
If you now go to a Markdown page on Github and click the bookmark it will reformat the page and change the CSS so that it looks the same as on screen when you print. Now just print the page.
Bookmarklet contents:
javascript:(function(e,a,g,h,f,c,b,d)%7Bif(!(f=e.jQue...
gdb fails with “Unable to find Mach task port for process-id” error
...
In Snow Leopard and later Mac OS versions, it isn't enough to codesign the gdb executable.
You have to follow this guide to make it work: http://www.opensource.apple.com/source/lldb/lldb-69/docs/code-signing.txt
The guide explains how to d...
What could cause java.lang.reflect.InvocationTargetException?
Well, I've tried to understand and read what could cause it but I just can't get it:
13 Answers
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CSS does the width include the padding?
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IE used to use the more-convenient-but-non-standard "border-box" box model. In this model, the width of an element includes the padding and borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing brow...
Git: Cannot see new remote branch
A colleague pushed a new remote branch to origin/dev/homepage and I cannot see it when I run:
9 Answers
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How to convert SecureString to System.String?
...you can access the raw data using Marshal.ReadInt16(IntPtr, Int32):
void HandleSecureString(SecureString value) {
IntPtr valuePtr = IntPtr.Zero;
try {
valuePtr = Marshal.SecureStringToGlobalAllocUnicode(value);
for (int i=0; i < value.Length; i++) {
short unicodeChar = Marshal....
How to convert std::string to NSString?
Hi I am trying to convert a standard std::string into an NSString but I'm not having much luck.
6 Answers
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Clear a terminal screen for real
Using the clear command on the terminal only fools the user into thinking the screen has been cleared...you can still see output from the previous commands when you scroll using the mouse. This makes life difficult when you are drowning in a tsunami of text.
...
What is the yield keyword used for in C#?
...uced in C# 2.0. In earlier versions you had to create your own IEnumerable and IEnumerator objects to do stuff like this.
The easiest way understand code like this is to type-in an example, set some breakpoints and see what happens. Try stepping through this example:
public void Consumer()
{
f...