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Can someone give an example of cosine similarity, in a very simple, graphical way?
... want to know how similar these texts are, purely in terms of word counts (and ignoring word order). We begin by making a list of the words from both texts:
me Julie loves Linda than more likes Jane
Now we count the number of times each of these words appears in each text:
me 2 2
Jane ...
How to randomize (or permute) a dataframe rowwise and columnwise?
...,]
> df2
a b c
3 0 1 0
4 0 0 0
2 1 0 0
1 1 1 0
By default sample() randomly reorders the elements passed as the first argument. This means that the default size is the size of the passed array. Passing parameter replace=FALSE (the default) to sample(...) ensures that sampling is done withou...
What XML parser should I use in C++? [closed]
I have XML documents that I need to parse and/or I need to build XML documents and write them to text (either files or memory). Since the C++ standard library does not have a library for this, what should I use?
...
How to write inline if statement for print?
...n Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly when you write
x = a if b else 0
it means
x = ...
Switch statement fallthrough in C#?
... Damn - I've been programming with C# since the early days of 1.0, and I've never seen this until now. Just goes to show, you learn new things every day.
– Erik Forbes
Feb 5 '09 at 3:30
...
Purge or recreate a Ruby on Rails database
...ave a dev Ruby on Rails database full of data. I want to delete everything and rebuild the database. I'm thinking of using something like:
...
What are the pros and cons of performing calculations in sql vs. in your application
...ed to access/aggregate a lot of data, doing it at the db server will save bandwidth, and disk io if the aggregates can be done inside indexes)
convenience (sql is not the best language for complex work - especially not great for procedural work, but very good for set-based work; lousy error-handling...
The definitive guide to form-based website authentication [closed]
...tion. The sections below will deal with patterns for sound practical auth, and how to avoid the most common security pitfalls.
To HTTPS or not to HTTPS?
Unless the connection is already secure (that is, tunneled through HTTPS using SSL/TLS), your login form values will be sent in cleartext, which al...
Change date of git tag (or GitHub Release based on it)
...Go back in time to the commit representing the tag
Delete the tag (locally and remotely)
This will turn your "Release" on GitHub into a Draft that you can later delete.
Re-add the same-named tag using a magic invocation that sets its date to the date of the commit.
Push the new tags with fixed da...
What does the “yield” keyword do?
What is the use of the yield keyword in Python, and what does it do?
42 Answers
42
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