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Any implementation of Ordered Set in Java?
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answered Jan 3 '12 at 13:08
Chandra SekharChandra Sekhar
14.8k1010 gold badges6666 silver badges8686 bronze badges
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What's the fastest way to merge/join data.frames in R?
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DF1 = data.frame(a = c(1, 1, 2, 2), b = 1:4)
DF2 = data.frame(b = c(1, 2, 3, 3, 4), c = letters[1:5])
merge(DF1, DF2)
b a c
1 1 1 a
2 2 1 b
3 3 2 c
4 3 2 d
5 4 2 e
DF1$c = DF2$c[match(DF1$b, DF2$b)]
DF1$c
[1] a b c e
Levels: a b c d e
> DF1
a b c
1 1 1 a
2 1 2 b
3 2 3 c
4 2 4 e
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Determine Whether Integer Is Between Two Other Integers?
...other integers (e.g. greater than/equal to 10000 and less than/equal to 30000 )?
11 Answers
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List comprehension rebinds names even after scope of comprehension. Is this right?
...omprehensions leak the loop control variable in Python 2 but not in Python 3. Here's Guido van Rossum (creator of Python) explaining the history behind this:
We also made another change in Python
3, to improve equivalence between list
comprehensions and generator
expressions. In Python 2,...
Force point (“.”) as decimal separator in java
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answered Mar 8 '11 at 17:32
Jon SkeetJon Skeet
1211k772772 gold badges85588558 silver badges88218821 bronze badges
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What does the tilde (~) mean in my composer.json file?
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3 Answers
3
Active
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Algorithm to find Largest prime factor of a number
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134
Actually there are several more efficient ways to find factors of big numbers (for smaller ones...
Return multiple columns from pandas apply()
...ue) + ' MB'
s['size_gb'] = locale.format("%.1f", s['size'] / 1024.0 ** 3, grouping=True) + ' GB'
return s
df_test = df_test.append(rows_list)
df_test = df_test.apply(sizes, axis=1)
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Create a dictionary with list comprehension
...sion:
{key: value for (key, value) in iterable}
Note: this is for Python 3.x (and 2.7 upwards). Formerly in Python 2.6 and earlier, the dict built-in could receive an iterable of key/value pairs, so you can pass it a list comprehension or generator expression. For example:
dict((key, func(key)) fo...