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What are the “standard unambiguous date” formats for string-to-date conversion in R?
... '"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn't one of the two listed above. as.Date("01/01/2000") yields an incorrect answer because the date isn't in one of the two fo...
how to generate migration to make references polymorphic
I have a Products table and want to add a column:
4 Answers
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How do you check in python whether a string contains only numbers?
...u'll want to use the isdigit method on your str object:
if len(isbn) == 10 and isbn.isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits tha...
Change application's starting activity
I have created the meat and guts of my application but I want to add a different activity that will be the starting point (sort of a log-in screen).
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How to pause for specific amount of time? (Excel/VBA)
...se the Wait method:
Application.Wait Now + #0:00:01#
or (for Excel 2010 and later):
Application.Wait Now + #12:00:01 AM#
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BroadcastReceiver with multiple filters or multiple BroadcastReceivers?
I have an Android Activity that needs to catch two different broadcasts. My current approach is to have a single BroadcastReceiver within the Activity and catch both the broadcasts with it:
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Find element's index in pandas Series
... answer. How can I get the index of certain element of a Series in python pandas? (first occurrence would suffice)
10 Answe...
Best way to pretty print a hash
I have a large hash with nested arrays and hashes. I would like to simply print it out so it 'readable' to the user.
12 An...
Change case of a file on Windows?
... becomes SourceCode.java , for example. The catch: I'm on a Windows box, and the filesystem thinks those are the same file name.
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Why is MySQL's default collation latin1_swedish_ci?
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He is Finnish , but Finnish and Swedish share almost the same special characters ,so they share the same case insensitive collation
– kommradHomer
Feb 26 '14 at 10:47
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