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Convert a list to a data frame
...x means that all data will be coerced into a common type. I.e. if you have one column of character data and one column of numeric data the numeric data will be coerced to string by matrix() and then both to factor by data.frame().
– Ian Sudbery
Mar 15 '13 at 10...
In Python how should I test if a variable is None, True or False
I have a function that can return one of three things:
6 Answers
6
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How do I use cascade delete with SQL Server?
I have 2 tables: T1 and T2, they are existing tables with data. We have a one to many relationship between T1 and T2. How do I alter the table definitions to perform cascading delete in SQL Server when a record from T1 is deleted, all associated records in T2 also deleted.
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What is “String args[]”? parameter in main method Java
...String objects.
In other words, if you run your program as java MyProgram one two then args will contain ["one", "two"].
If you wanted to output the contents of args, you can just loop through them like this...
public class ArgumentExample {
public static void main(String[] args) {
fo...
How to check if a map contains a key in Go?
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One line answer:
if val, ok := dict["foo"]; ok {
//do something here
}
Explanation:
if statements in Go can include both a condition and an initialization statement. The example above uses both:
initializes two vari...
tmux: How to join two tmux windows into one, as panes?
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Actually join-pane is to move one pane into another, not to move window. join-pane -s 2 -t 1 does not put two windows side by side, but two panes instead. It's just that the windows happen to have only one pane each. If you have two windows both of which ...
How to configure git push to automatically set upstream without -u?
... to keep in mind that this does not make the local branch track the remote one; it just creates the remote branch with the same name as the local one.
– waldyrious
Mar 15 '19 at 12:20
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document.getElementById vs jQuery $()
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For anyone interested document.getElementBy doesn't work correctly in <IE8. It also gets elements by name therefore you could theoretically argue document.getElementById is not only misleading, but can return incorrect values. ...
Live-stream video from one android phone to another over WiFi
...r days now on how to implement a video streaming feature from an android phone to another android phone over a WiFi connection but I can't seem to find anything useful. I looked on android developers for sample code, stackoverflow, google, android blogs but nothing. All I can find are some sort of p...
Best way to include CSS? Why use @import?
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For those who are curious: one of my favorite uses of @import is when you have a build process set up using something like grunt-concat-css. During development, the @import statements work and page load speed isn't a concern. Then, when you're building...