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What is the best Java email address validation method? [closed]
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19 Answers
19
Active
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How can I get a list of locally installed Python modules?
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+100
Solution
Do not use with pip > 10.0!
My 50 cents for getting a pip freeze-like list from a Python script:
import pip
installed...
Convert the values in a column into row names in an existing data frame
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138
This should do:
samp2 <- samp[,-1]
rownames(samp2) <- samp[,1]
So in short, no there ...
How do you round to 1 decimal place in Javascript?
Can you round a number in javascript to 1 character after the decimal point (properly rounded)?
21 Answers
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How is set() implemented?
I've seen people say that set objects in python have O(1) membership-checking. How are they implemented internally to allow this? What sort of data structure does it use? What other implications does that implementation have?
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What is the difference between Python's list methods append and extend?
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append: Appends object at the end.
x = [1, 2, 3]
x.append([4, 5])
print (x)
gives you: [1, 2, 3, [4, 5]]
extend: Extends list by appending elements from the iterable.
x = [1, 2, 3]
x.extend([4, 5])
print (x)
gives you: [1, 2, 3, 4, 5]
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Are trailing commas in arrays and objects part of the spec?
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212
Specs: ECMAScript 5 and ECMAScript 3
Section 11.1.5 in the ECMAScript 5 specification:
Obj...
CSS I want a div to be on top of everything
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122
In order for z-index to work, you'll need to give the element a position:absolute or a positio...