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Convert a matrix to a 1 dimensional array
I have a matrix (32X48).
10 Answers
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How to Correctly Use Lists in R?
...ints out the difference between a list and vector in R:
Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data fram...
Remove unwanted parts from strings in a column
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data['result'] = data['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))
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Using Pairs or 2-tuples in Java [duplicate]
...but a custom one might be as easy as the following:
public class Tuple<X, Y> {
public final X x;
public final Y y;
public Tuple(X x, Y y) {
this.x = x;
this.y = y;
}
}
Of course, there are some important implications of how to design this class further regarding equa...
case-insensitive list sorting, without lowercasing the result?
...trings, since they both have a lower method.
In Python 2 it works for a mix of normal and unicode strings, since values of the two types can be compared with each other. Python 3 doesn't work like that, though: you can't compare a byte string and a unicode string, so in Python 3 you should do the s...
Changing my CALayer's anchorPoint moves the view
...r Geometry and Transforms section of the Core Animation Programming Guide explains the relationship between a CALayer's position and anchorPoint properties. Basically, the position of a layer is specified in terms of the location of the layer's anchorPoint. By default, a layer's anchorPoint is (0....
Is R's apply family more than syntactic sugar?
...regarding execution time and / or memory.
5 Answers
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How to linebreak an svg text within javascript?
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This is not something that SVG 1.1 supports. SVG 1.2 does have the textArea element, with automatic word wrapping, but it's not implemented in all browsers. SVG 2 does not plan on implementing textArea, but it does have auto-wrapped text.
However, given that you already know where your linebr...
What does the 'b' character do in front of a string literal?
Apparently, the following is the valid syntax:
8 Answers
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Understanding Python's “is” operator
...the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1, 2, 3]
print(x == y) # prints Fals...