Difference between revisions of "Cookbook/Dates And Time"
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m (→Difference of two dates: typo) |
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import Date.Time |
import Date.Time |
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a = fromGregorian 2009 12 31 --> 2009-12-31 |
a = fromGregorian 2009 12 31 --> 2009-12-31 |
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− | b = fromGregorian 2010 12 |
+ | b = fromGregorian 2010 12 31 --> 2010-12-31 |
diffDays b a --> 365 |
diffDays b a --> 365 |
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</haskell> |
</haskell> |
Revision as of 17:45, 2 August 2009
Finding today's date
import Data.Time
c <- getCurrentTime --> 2009-04-21 14:25:29.5585588 UTC
(y,m,d) = toGregorian $ utctDay c --> (2009,4,21)
Adding to or subtracting from a date
Problem | Solution | Examples |
---|---|---|
adding days to a date | addDays | import Date.Time
a = fromGregorian 2009 12 31 --> 2009-12-31
b = addDays 1 a --> 2010-01-01
|
subtracting days from a date | addDays | import Date.Time
a = fromGregorian 2009 12 31 --> 2009-12-31
b = addDays (-7) a --> 2009-12-24
|
Difference of two dates
Problem | Solution | Examples |
---|---|---|
calculating the difference of two dates | diffDays | import Date.Time
a = fromGregorian 2009 12 31 --> 2009-12-31
b = fromGregorian 2010 12 31 --> 2010-12-31
diffDays b a --> 365
|
CPU time
Use System.CPUTime.getCPUTime to get the CPU time in picoseconds.
You can time a computation like this
getCPUTimeDouble :: IO Double
getCPUTimeDouble = do t <- System.CPUTime.getCPUTime; return ((fromInteger t) * 1e-12)
main = do
t1 <- getCPUTimeDouble
print (fib 30)
t2 <- getCPUTimeDouble
print (t2-t1)