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What are the differences between vector and list data types in R?
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Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
.net implementation of bcrypt
...han BCrypt.dll or it will conflict with the new Windows API in Vista that calls functions in a 'bcrypt.dll', so if you have Bcrypt.net as Bcrypt.dll in your web app bin/ directory Windows won't be able to find the correct dll and you will get some cryptic errors.
– thelsdj
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How do I rename a column in a database table using SQL?
...N MyOldColumn;
For the very simplest of cases (no constraints, triggers, indexes or keys), it will take the above 3 lines. For anything more complicated it can get very messy as you fill in the missing parts.
However, as mentioned above, there are simpler database specific methods if you know whi...
Is this a “good enough” random algorithm; why isn't it used if it's faster?
I made a class called QuickRandom , and its job is to produce random numbers quickly. It's really simple: just take the old value, multiply by a double , and take the decimal part.
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Why use multiple columns as primary keys (composite primary key)
..." link is particularly stupid, the info is self-serving and false. 2) The index on the columns that make the row unique cannot be avoided. A "surrogate" ID with an index is always an additional column and an additional index. Rather silly because it is redundant. And slower.
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Can you help me understand this? “Common REST Mistakes: Sessions are irrelevant”
...ature of HTTP.
Okay, I get that HTTP authentication
is done automatically on every message
- but how?
Yes, the username and password is sent with every request. The common methods to do so are basic access authentication and digest access authentication. And yes, an eavesdropper can capt...
In Python, when to use a Dictionary, List or Set?
... and x not in l
l[i], l[i:j], l[i:j:k]
len(l), min(l), max(l)
l.count(x)
l.index(x[, i[, j]]) - index of the 1st occurrence of x in l (at or after i and before j indeces)
A list also implements all of the mutable sequence operations:
l[i] = x - item i of l is replaced by x
l[i:j] = t - slice of ...
Heatmap in matplotlib with pcolor?
...pen("http://datasets.flowingdata.com/ppg2008.csv")
nba = pd.read_csv(page, index_col=0)
# Normalize data columns
nba_norm = (nba - nba.mean()) / (nba.max() - nba.min())
# Sort data according to Points, lowest to highest
# This was just a design choice made by Yau
# inplace=False (default) ->tha...
Blocks and yields in Ruby
... Let's simplify that a bit: File.readlines("readfile.rb").each_with_index do |line, index| puts "#{index + 1}: #{line}" end and laugh even harder at the Java guys.
– Michael Hampton
Dec 29 '14 at 4:17
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z-index not working with position absolute
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The second div is position: static (the default) so the z-index does not apply to it.
You need to position (set the position property to anything other than static, you probably want relative in this case) anything you want to give a z-index to.
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