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Type List vs type ArrayList in Java [duplicate]
I understand that with (1), implementations of the List interface can be swapped. It seems that (1) is typically used in an application regardless of need (myself I always use this).
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Printf width specifier to maintain precision of floating-point value
...eventh = 1.0/7.0 results in the value below. Also shown are the preceding and following representable double floating point numbers.
OneSeventh before = 0.1428571428571428 214571170656199683435261249542236328125
OneSeventh = 0.1428571428571428 49212692681248881854116916656494140625
OneSeven...
Tuples( or arrays ) as Dictionary keys in C#
...alues to one string. I tried using arrays as keys, but that did not work, and I don't know what else to do. At this point I am considering making a Dictionary of Dictionaries of Dictionaries, but that would probably not be very pretty to look at, though it is how I would do it in javascript.
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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...y ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labe...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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@Smith I meant using plain UPDATE and INSERT statements and checking return value.
– codeholic
Nov 17 '13 at 14:47
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CSS: Control space between bullet and
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@Wolle Hmmm. It's an old comment, and I'm not sure of the concern -- If it's as to whether <SPAN> can utilize id or class tags, take a look at W3C. If the question is whether it can convey semantic meaning, see this answer. Technically, the <SPAN>...
How to set 'auto' for upper limit, but keep a fixed lower limit with matplotlib.pyplot
...t to keep the lower limit of the y-axis to always be zero. I tried 'auto' and 'autorange', but those don't seem to work. Thank you in advance.
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A simple scenario using wait() and notify() in java
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The wait() and notify() methods are designed to provide a mechanism to allow a thread to block until a specific condition is met. For this I assume you're wanting to write a blocking queue implementation, where you have some fixed size ...
Select rows which are not present in other table
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There are basically 4 techniques for this task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
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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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