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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...
Synchronise ScrollView scroll positions - android
I have 2 ScrollViews in my android layout. How can I synchronise their scroll positions?
4 Answers
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PHP mail function doesn't complete sending of e-mail
...al pitfalls you may be encountering.
Make sure error reporting is enabled and set to report all errors
Error reporting is essential to rooting out bugs in your code and general errors that PHP encounters. Error reporting needs to be enabled to receive these errors. Placing the following code at th...
how to generate migration to make references polymorphic
I have a Products table and want to add a column:
4 Answers
4
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Throw keyword in function's signature
...ce this, so it has to be checked at runtime, which is usually undesirable. And it is not well supported in any case. (MSVC ignores exception specifications, except throw(), which it interprets as a guarantee that no exception will be thrown.
...
Rename a git submodule
...le directory (other than going through the entire motion of deleting it and re-adding it with a new destination name).
...
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...
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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扩展App Inventor：具有多点触控和手势检测功能 · App Inventor 2 中文网
...@mit.edu)
Hal Abelson (hal@mit.edu)
Department of Electrical Engineering and Computer Science
Massachusetts Institute of Technology
77 Massachusetts Avenue, Cambridge, MA 02139, USA
ABSTRACT
MIT App Inventor is a block-based event-driven programming tool that allows everyone, especially novice...
What does “SyntaxError: Missing parentheses in call to 'print'” mean in Python?
..."Missing parentheses in call to print" case is a compile time syntax error and hence has access to the raw source code, it's able to include the full text on the rest of the line in the suggested replacement. However, it doesn't currently try to work out the appropriate quotes to place around that e...