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Opening a folder in explorer and selecting a file
... edited Jul 26 '17 at 22:30
Winter
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answered Mar 30 '09 at 6:09
...
Pandas groupby: How to get a union of strings
...0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own function, there is not automatic exclusions of non-numeric columns. This is slower, though, than the application of .sum() to the groupby
In [8]: df.gro...
What is the purpose of setting a key in data.table?
...ses to list (i.e., they are equivalent). Internally when i is a list, it's converted to a data.table following which binary search is used to compute row indices. Fixed 1e4 to 1e5 to avoid confusion. Thanks for spotting. Note that we can directly use on= argument now to perform binary subsets rather...
Best explanation for languages without null
...find (_.firstName == "joe")) map (fullNameLength)
How does this work?
//convert an Option[List[Person]] to an Option[S]
//where the function f takes a List[Person] and returns an S
people map f
//find a person named "Joe" in a List[Person].
//returns Some[Person], or None if "Joe" isn't in the l...
HTML5: number input type that takes only integers?
...e thing. In the HTML5 specification, the input type "number" can have both integers and floating-point numbers. This seems incredibly short-sighted since it will only be a useful validator when your database fields are signed floating-point numbers (for unsigned ints you'll have to fall back to "pat...
Is String.Contains() faster than String.IndexOf()?
...r. But really the speed differences we're talking about are minute - the point is one calls the other, and Contains is more readable if you don't need the index. In other words don't worry about it.
– Chris S
Nov 15 '15 at 18:17
...
Upload file to FTP using C#
...m = request.GetRequestStream())
{
byte[] buffer = new byte[10240];
int read;
while ((read = fileStream.Read(buffer, 0, buffer.Length)) > 0)
{
ftpStream.Write(buffer, 0, read);
Console.WriteLine("Uploaded {0} bytes", fileStream.Position);
}
}
For GUI progress...
What is the simplest way to get indented XML with line breaks from XmlDocument?
...
Based on the other answers, I looked into XmlTextWriter and came up with the following helper method:
static public string Beautify(this XmlDocument doc)
{
StringBuilder sb = new StringBuilder();
XmlWriterSettings settings = new XmlWriterSettings
{
...
How to add a TextView to LinearLayout in Android
...
for(int j=0;j<30;j++) {
LinearLayout childLayout = new LinearLayout(MainActivity.this);
LinearLayout.LayoutParams linearParams = new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT,
LayoutParams.WR...
What's the use/meaning of the @ character in variable names in C#?
... added a web reference to my project) that was written in Java. One of the interface objects defined in the WSDL had a member variable with the name "params". Obviously this is a reserved word in C# so you can't have a class with a member variable with the name "params". The proxy object that was ge...