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How to determine day of week by passing specific date?
For Example I have the date: "23/2/2010" (23th Feb 2010). I want to pass it to a function which would return the day of week . How can I do this?
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Scala: Nil vs List()
...intln (Nil equals List())
true
scala> System.identityHashCode(Nil)
374527572
scala> System.identityHashCode(List())
374527572
Nil is more idiomatic and can be preferred in most cases.
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Fastest way to replace NAs in a large data.table
...e a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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Pad a string with leading zeros so it's 3 characters long in SQL Server 2008
...ring that is up to 3 characters long when it's first created in SQL Server 2008 R2.
17 Answers
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Python: Continuing to next iteration in outer loop
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72
for i in ...:
for j in ...:
for k in ...:
if something:
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How to convert an enum type variable to a string?
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SQL query for today's date minus two months
... select all the records in a table where their date of entry is older then 2 months.
5 Answers
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What's the opposite of head? I want all but the first N lines of a file
...xt file of unknown length, how can I read, for example all but the first 2 lines of the file? I know tail will give me the last N lines, but I don't know what N is ahead of time.
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Is R's apply family more than syntactic sugar?
...ntly different performance:
> fibo <- function(n) {
+ if ( n < 2 ) n
+ else fibo(n-1) + fibo(n-2)
+ }
> system.time(for(i in 0:26) fibo(i))
user system elapsed
7.48 0.00 7.52
> system.time(sapply(0:26, fibo))
user system elapsed
7.50 0.00 7.54
> s...
fork() branches more than expected?
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The fork() primitive often stretches the imagination. Until you get a feel for it, you should...