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What is an intuitive explanation of the Expectation Maximization technique? [closed]
... here.
Suppose we have some data sampled from two different groups, red and blue:
Here, we can see which data point belongs to the red or blue group. This makes it easy to find the parameters that characterise each group. For example, the mean of the red group is around 3, the mean of the blue...
How to reliably open a file in the same directory as a Python script
...ame directory as the currently running Python script by simply using a command like
5 Answers
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Which MySQL data type to use for storing boolean values
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For MySQL 5.0.3 and higher, you can use BIT. The manual says:
As of MySQL 5.0.3, the BIT data type is used to store bit-field
values. A type of BIT(M) enables storage of M-bit values. M can range
from 1 to 64.
Otherwise, according to the M...
Getting the first character of a string with $str[0]
I want to get the first letter of a string and I've noticed that $str[0] works great. I am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right –...
Why can't I center with margin: 0 auto?
I have a #header div that is 100% width and within that div I have an unordered list. I have applied margin: 0 auto to the unordered list but it won't center it within the header div.
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How do I get an object's unqualified (short) class name?
...thout its namespace.
First, you need to build a ReflectionClass instance, and then call the getShortName method of that instance:
$reflect = new ReflectionClass($object);
if ($reflect->getShortName() === 'Name') {
// do this
}
However, I can't imagine many circumstances where this would b...
How to create a UIView bounce animation?
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With iOS7 and UIKit Dynamics, there is no longer any need to use CAKeyframeAnimations or UIView animations!
Take a look at Apple's UIKit Dynamics Catalog app. Alternately, Teehanlax has a clear, concise tutorial with the full project ...
Difference between InvariantCulture and Ordinal string comparison
...trings in c# for equality, what is the difference between InvariantCulture and Ordinal comparison?
9 Answers
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In javascript, is an empty string always false as a boolean?
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Yes. Javascript is a dialect of ECMAScript, and ECMAScript language specification clearly defines this behavior:
ToBoolean
The result is false if the argument is the empty String (its length is zero);
otherwise the result is true
Quote taken from http://www.ecma-inte...
What is the difference between svg's x and dx attribute?
What is the difference between svg's x and dx attribute (or y and dy)? When would be a proper time to use the axis shift attribute (dx) versus the location attribute (x)?
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