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Counting the number of elements with the values of x in a vector
...> a[names(a)==435]
435
3
Or convert it into a data.frame if you're more comfortable working with that:
> as.data.frame(table(numbers))
numbers Freq
1 4 2
2 5 1
3 23 2
4 34 2
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Difference between scaling horizontally and vertically for databases [closed]
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Horizontal scaling means that you scale by adding more machines into your pool of resources whereas Vertical scaling means that you scale by adding more power (CPU, RAM) to an existing machine.
An easy way to remember this is to think of a machine on a server rack, we add mo...
Looping through the content of a file in Bash
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How do I display a text file content in CMD?
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You can use the more command. For example:
more filename.txt
Take a look at GNU utilities for Win32 or download it:
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How can I quantify difference between two images?
... want to normalize images.
But be careful, in some situations this may do more wrong than good. For example, a single bright pixel on a dark background will make the normalized image very different.
Is color information important?
If you want to notice color changes, you will have a vector of colo...
What's so bad about Template Haskell?
...ts a [Char] or a (a -> (forall b . b -> c)) or whatever. TH would be more reliable if one could express that a function may only generate expressions of a certain type, or only function declarations, or only data-constructor-matching patterns, etc.
You can generate expressions that don't compi...
How to choose between Hudson and Jenkins? [closed]
...Jan/2011)
I have no idea how rapid the change of each branch is now, but more importantly, what is the direction each branch is taking and what are key points so one could make a choice between which to go with?
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Can a java file have more than one class?
What is the purpose of having more than one class in a Java file ? I am new to Java.
18 Answers
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Understanding “randomness”
I can't get my head around this, which is more random?
28 Answers
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What is the difference between Builder Design pattern and Factory Design pattern?
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With design patterns, there usually is no "more advantageous" solution that works for all cases. It depends on what you need to implement.
From Wikipedia:
Builder focuses on constructing a
complex object step by step. Abstract
Factory emphasizes a family ...