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Delete column from pandas DataFrame
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This answer isn't really correct - the pandas developers didn't, but that doesn't mean it is hard to do.
– wizzwizz4
Sep 30 '17 at 9:42
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What are “connecting characters” in Java identifiers?
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I'm not sure that actually fully answers the (implied) question of which characters may start a Java identifier. Following links we end up at Character.isJavaIdentifierStart() which states A character may start a Java identifier if and only if one...
Open URL in same window and in same tab
...ute target= of tag a. In fact, you can name your window whatever you like. All what you need is set it different value, so that it won't open in the same window or tab.
– ijse
Dec 10 '11 at 14:57
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How to take the first N items from a generator or list in Python? [duplicate]
...imple syntax: array[start:stop:step]
You can omit any parameter. These are all valid: array[start:], array[:stop], array[::step]
Slicing a generator
import itertools
top5 = itertools.islice(my_list, 5) # grab the first five elements
You can't slice a generator directly in Python. itertools.i...
Regular expression for letters, numbers and - _
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To actually cover your pattern, i.e, valid file names according to your rules, I think that you need a little more. Note this doesn't match legal file names from a system perspective. That would be system dependent and more libera...
Number of elements in a javascript object
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Although JS implementations might keep track of such a value internally, there's no standard way to get it.
In the past, Mozilla's Javascript variant exposed the non-standard __count__, but it has been removed with version 1.8.5.
For cross-browser scripting you're stuck with explicitly ite...
Is there a way to make GHC provide the type class constraints of typed holes?
...ng out-of-scope types
(use -fprint-potential-instances to see them all)
• In the expression: show _
In an equation for ‘it’: it = show _
<interactive>:3:6: error:
• Found hole: _ :: a0
Where: ‘a0’ is an ambiguous type variable
• In the first argum...
What is a higher kinded type in Scala?
...pply to value arguments to "construct" a value.
Value constructors are usually called "functions" or "methods". These "constructors" are also said to be "polymorphic" (because they can be used to construct "stuff" of varying "shape"), or "abstractions" (since they abstract over what varies between ...
Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...
What is the difference between “px”, “dip”, “dp” and “sp”?
...lems with dp while everything works fine with dip
– DallaRosa
Jul 4 '11 at 6:07
255
One note abou...