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Python Pandas merge only certain columns
...e to only merge some columns? I have a DataFrame df1 with columns x, y, z, and df2 with columns x, a ,b, c, d, e, f, etc.
5...
How can I rename a project folder from within Visual Studio?
... the extra steps required.
To rename a project's folder, file (.*proj) and display name in Visual Studio:
Close the solution.
Rename the folder(s) outside Visual Studio. (Rename in TFS if using source control)
Open the solution, ignoring the warnings (answer "no" if asked to load a project fro...
Is there a way to pass optional parameters to a function?
...a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
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How do you downgrade rubygems?
...ve rubygems 1.3.1 installed but I want to go back to 1.2.0. What's the command to downgrade rubygems?
6 Answers
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List all tables in postgresql information_schema
...asterisk).(asterisk) thing, sorry. I just ran the select query in postgres and it listed information about all the tables in it. Try running the select statement (on your blank db) and see what it returns.
– RodeoClown
Feb 16 '10 at 22:15
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How to create a backup of a single table in a postgres database?
...way to create a backup of a single table within a database using postgres? And how? Does this also work with the pg_dump command?
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How do I run all Python unit tests in a directory?
... that will, you guessed it, run all files in the aforementioned test form and return the result. I have tried two methods so far; both have failed. I will show the two methods, and I hope someone out there knows how to actually do this correctly.
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How to print out the contents of a vector?
... a supplement to the above iterator solution. If you are using the C++11 standard (or later), then you can use the auto keyword to help the readability:
for (auto i = path.begin(); i != path.end(); ++i)
std::cout << *i << ' ';
But the type of i will be non-const (i.e., the compiler ...
How do I find out which DOM element has the focus?
...ript, which element currently has focus. I've been looking through the DOM and haven't found what I need, yet. Is there a way to do this, and how?
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c# open a new form then close the current form?
...urrent form is disposed together with form2. Therefore you need to hide it and set form2.Closed event to call this.Close().
private void OnButton1Click(object sender, EventArgs e)
{
this.Hide();
var form2 = new Form2();
form2.Closed += (s, args) => this.Close();
form2.Show();
}
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