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Adding a column to a data.frame

...number of groups (x in mapply) and its length (y in mapply) mytb<-read.table(text="h_no h_freq h_freqsq group 1 0.09091 0.008264628 1 2 0.00000 0.000000000 1 3 0.04545 0.002065702 1 4 0.00000 0.000000000 1 1 0.13636 0.018594050 2 2 0.00000 0.000000000 2 3 0.00000 ...
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Regex lookahead, lookbehind and atomic groups

...ely follow, and stop as backtracking is disabled A non-atomic group will allow backtracking; if subsequent matching ahead fails, it will backtrack and use alternative patterns until a match for the entire expression is found or all possibilities are exhausted. (foo|foot)s applied to foots will: ...
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Detecting Unsaved Changes

...reunload methods as required. From the comments, the following references all input fields, without duplicating code: $(':input').change(function () { Using $(":input") refers to all input, textarea, select, and button elements. ...
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Check if OneToOneField is None in Django

... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
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res.sendFile absolute path

...pond with index.html on every request, because I'm using a star * to catch all files that weren't found in your static (public) directory; which is the most common use case for web-apps. Change to / to return the index only in the root path. ...
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Declare and initialize a Dictionary in Typescript

... Very helpful sample code. The "interface IDictionary" contains a small typo, as there is a reference to IPerson. – mgs Apr 9 '13 at 5:31 ...
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Obstructed folders in Subversion

...swered Mar 2 '12 at 16:09 Bobby TablesBobby Tables 81611 gold badge77 silver badges1717 bronze badges ...
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Any gotchas using unicode_literals in Python 2.6?

...wo.name The output of running python one.py is: Traceback (most recent call last): File "one.py", line 5, in <module> print name + two.name UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 4: ordinal not in range(128) In this example, two.name is an utf-8 encoded...
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Are the shift operators () arithmetic or logical in C?

...h may lead to implementation-defined behaviour if the value is not representable in the destination type. Left Shift The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated bits are filled with zeros. If E1 has an unsigned type, the value of the result is E1×2E2, reduced modulo o...
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What is the difference between BIT and TINYINT in MySQL?

...thing on linux, I had problems with queries that inserted or selected from tables that had BIT DATA TYPE. Bit is not safe for now. I changed to tinyint(1) and worked perfectly. I mean that you only need a value to diferentiate if it's 1 or 0 and tinyint(1) it's ok for that ...