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What is the relative performance difference of if/else versus switch statement in Java?
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That's micro optimization and premature optimization, which are evil. Rather worry about readabililty and maintainability of the code in question. If there are more than two if/else blocks glued together or its size is unpredictable, then you may high...
Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
I guess I'm not clear on how to do "and" tests. I wanted to make sure an argument existed which was working well with [ -e $VAR ] , but it turns out that was also evaluating as true on an empty string; which I do not want.
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Efficient way to insert a number into a sorted array of numbers?
I have a sorted JavaScript array, and want to insert one more item into the array such the resulting array remains sorted. I could certainly implement a simple quicksort-style insertion function:
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What does value & 0xff do in Java?
... not quite. The & operator works on long values as well, if either operand is a long. But not on byte. See the Java Language Specification, sections 15.22.1 and 5.6.2.
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generate days from date range
...es, or temp tables. The subquery generates dates for the last 10,000 days, and could be extended to go as far back or forward as you wish.
select a.Date
from (
select curdate() - INTERVAL (a.a + (10 * b.a) + (100 * c.a) + (1000 * d.a) ) DAY as Date
from (select 0 as a union all select 1 un...
Find row where values for column is maximal in a pandas DataFrame
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Use the pandas idxmax function. It's straightforward:
>>> import pandas
>>> import numpy as np
>>> df = pandas.DataFrame(np.random.randn(5,3),columns=['A','B','C'])
>>> df
A B ...
Mac SQLite editor [closed]
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Hangs on slow running queries and had no cancel query button. I use RazorSQL.
– wioota
Jan 3 '09 at 17:49
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What is the difference between JavaScript and ECMAScript?
What's the difference between ECMAScript and JavaScript? From what I've deduced, ECMAScript is the standard and JavaScript is the implementation. Is this correct?
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Purpose of Unions in C and C++
...ed unions earlier comfortably; today I was alarmed when I read this post and came to know that this code
15 Answers
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Declaring and initializing variables within Java switches
... block in which the declaration appears, starting with its own initializer and including any further declarators to the right in the local variable declaration statement.
In your case, case 2 is in the same block as case 1 and appears after it, even though case 1 will never execute... so the local...