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Is there a math nCr function in python? [duplicate]
...ython 2
As of Python 3.8, binomial coefficients are available in the standard library as math.comb:
>>> from math import comb
>>> comb(10,3)
120
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nginx error “conflicting server name” ignored [closed]
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I assume that you're running a Linux, and you're using gEdit to edit your files. In the /etc/nginx/sites-enabled, it may have left a temp file e.g. default~ (watch the ~).
Depending on your editor, the file could be named .save or something like it. Just run $ ...
Single script to run in both Windows batch and Linux Bash?
...rite a single script file which executes in both Windows (treated as .bat) and Linux (via Bash)?
11 Answers
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What is a stack trace, and how can I use it to debug my application errors?
...ject.Book.getTitle(Book.java:16)
To debug this, we can open up Book.java and look at line 16, which is:
15 public String getTitle() {
16 System.out.println(title.toString());
17 return title;
18 }
This would indicate that something (probably title) is null in the above code.
Exam...
form_for but to post to a different action
...> {:controller => 'my_controller', :action => 'my_action'}%>
and then in the form partial use this local variable like this:
<%= form_for(:post, :url => url_for(:controller => locals[:controller], :action => locals[:action]), html: {class: ""} ) do |f| -%>
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Possible to iterate backwards through a foreach?
I know I could use a for statement and achieve the same effect, but can I loop backwards through a foreach loop in C#?
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
...nager.getReference(LObj.getClass(), LObj.getId()) to get a database entity and then pass the returned object to be persisted in another table.
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How do I delete rows in a data frame?
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The key idea is you form a set of the rows you want to remove, and keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" ...
How to show only next line after the matched one?
Thanks to this command for every line that has 'blah' in it, I get the output of the line that contains 'blah' and the next line that follows in the logfile. It might be a simple one but I can't find a way to omit the line that has 'blah' and only show next line in the output.
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How to set the width of a cell in a UITableView in grouped style
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A better and cleaner way to achieve this is subclassing UITableViewCell and overriding its -setFrame: method like this:
- (void)setFrame:(CGRect)frame {
frame.origin.x += inset;
frame.size.width -= 2 * inset;
[super setFr...