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R - Concatenate two dataframes?
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227
You want "rbind".
b$b <- NA
new <- rbind(a, b)
rbind requires the data frames to have...
Is ASCII code 7-bit or 8-bit?
...d me ASCII is 8-bit character coding scheme. But it is defined only for 0-127 codes which means it can be fit into 7-bits. So can't it be argued that ASCII bit is actually 7-bit code?
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Extract first item of each sublist
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201
Using list comprehension:
>>> lst = [['a','b','c'], [1,2,3], ['x','y','z']]
>>...
`elif` in list comprehension conditionals
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259
Python's conditional expressions were designed exactly for this sort of use-case:
>>>...
Python - abs vs fabs
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127
math.fabs() converts its argument to float if it can (if it can't, it throws an exception). It ...
Implementing slicing in __getitem__
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121
The __getitem__() method will receive a slice object when the object is sliced. Simply look at ...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
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492
Yes, the order of elements in a python list is persistent.
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How can I plot with 2 different y-axes?
...that each set of points has its own (different) y-axis (i.e., in positions 2 and 4 on the figure) but the points appear superimposed on the same figure.
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NameError: global name 'xrange' is not defined in Python 3
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You are trying to run a Python 2 codebase with Python 3. xrange() was renamed to range() in Python 3.
Run the game with Python 2 instead. Don't try to port it unless you know what you are doing, most likely there will be more problems beyond xrange() vs. ...
Call by name vs call by value in Scala, clarification needed
... => Int).
def callByValue(x: Int) = {
println("x1=" + x)
println("x2=" + x)
}
def callByName(x: => Int) = {
println("x1=" + x)
println("x2=" + x)
}
Now what happens when we call them with our side-effecting function?
scala> callByValue(something())
calling something
x1=1
x2=1
...