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What is the difference between HashSet and List?
...and hashSet2
//returns a list of distinct items in both sets
HashSet set3 = set1.Union( set2 );
flies in comparison with an equivalent operation using LINQ. It's also neater to write!
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How can I format a decimal to always show 2 decimal places?
...s Decimal('0.01')
>>> # Round to two places
>>> Decimal('3.214').quantize(TWOPLACES)
Decimal('3.21')
>>> # Validate that a number does not exceed two places
>>> Decimal('3.21').quantize(TWOPLACES, context=Context(traps=[Inexact]))
Decimal('3.21')
>>> Deci...
When to use ' (or quote) in Lisp?
... passed to it are evaluated. This means you can write this:
(* (+ a 2)
3)
Which in turn evaluates (+ a 2), by evaluating a and 2. The value of the symbol a is looked up in the current variable binding set, and then replaced. Say a is currently bound to the value 3:
(let ((a 3))
(* (+ a 2)
...
Read stream twice
...
Captain Man
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answered Feb 29 '12 at 14:59
Paul GrimePaul Grime
...
Precision String Format Specifier In Swift
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JdbcTemplate queryForInt/Long is deprecated in Spring 3.2.2. What should it be replaced by?
... queryforInt/queryforLong methods in JdbcTemplate are deprecated in Spring 3.2. I can't find out why or what is considered the best practice to replace existing code using these methods.
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Why don't structs support inheritance?
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edited Oct 9 '15 at 11:53
nevermind
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answered Aug 3 '09 at 16...
Find integer index of rows with NaN in pandas dataframe
...n use to index back into df, e.g.:
df['a'].ix[index[0]]
>>> 1.452354
For the integer index:
df_index = df.index.values.tolist()
[df_index.index(i) for i in index]
>>> [3, 6]
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Why does the order of the loops affect performance when iterating over a 2D array?
...mensional. So while you imagine your array like this:
0,0 | 0,1 | 0,2 | 0,3
----+-----+-----+----
1,0 | 1,1 | 1,2 | 1,3
----+-----+-----+----
2,0 | 2,1 | 2,2 | 2,3
Your computer stores it in memory as a single line:
0,0 | 0,1 | 0,2 | 0,3 | 1,0 | 1,1 | 1,2 | 1,3 | 2,0 | 2,1 | 2,2 | 2,3
In the 2...
Why isn't my Pandas 'apply' function referencing multiple columns working? [closed]
...
381
Seems you forgot the '' of your string.
In [43]: df['Value'] = df.apply(lambda row: my_test(r...
