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Remove the last line from a file in Bash
...d for deleting a line, while $ means "the last line in the file". When specifying a location (called "range" in sed lingo) before a command, that command is only applied to the specified location. So, this command explicitly says "in the range of the last line in a file, delete it". Quite slick and ...
Multiline for WPF TextBox
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hey @itowlson if I creating multiline textbox with your method its work better but if I want to set textbox text counter label1.Content = textBox1.Text.Length; with this line its work but when I press enter in the textbox counter will incr...
How to concatenate columns in a Postgres SELECT?
... mean "returns NULL". The result of anything concatenated to NULL is NULL. If NULL values can be involved and the result shall not be NULL, use concat_ws() to concatenate any number of values (Postgres 9.1 or later):
SELECT concat_ws(', ', a, b) AS ab FROM foo;
Or concat() if you don't need separ...
How to generate a random integer number from within a range
... answers so far are mathematically wrong. Returning rand() % N does not uniformly give a number in the range [0, N) unless N divides the length of the interval into which rand() returns (i.e. is a power of 2). Furthermore, one has no idea whether the moduli of rand() are independent: it's possible...
Height of status bar in Android [duplicate]
...t() {
int result = 0;
int resourceId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resourceId > 0) {
result = getResources().getDimensionPixelSize(resourceId);
}
return result;
}
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Getting hold of the outer class object from the inner class object
... refer to any lexically enclosing instance, is described in the JLS as Qualified this.
I don't think there's a way to get the instance from outside the code of the inner class though. Of course, you can always introduce your own property:
public OuterClass getOuter() {
return OuterClass.this;
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Why does Ruby have both private and protected methods?
... never need to be called like this.
It is important to note that this is different from the way Java or C++ works. private in Ruby is similar to protected in Java/C++ in that subclasses have access to the method. In Ruby, there is no way to restrict access to a method from its subclasses like you ...
SQL keys, MUL vs PRI vs UNI
What is the difference between MUL , PRI and UNI in MySQL?
4 Answers
4
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How to add pandas data to an existing csv file?
I want to know if it is possible to use the pandas to_csv() function to add a dataframe to an existing csv file. The csv file has the same structure as the loaded data.
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Combine two or more columns in a dataframe into a new column with a new name
For example if I have this:
8 Answers
8
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