...s("5+5") [1] "character" > class(parse(text="5+5")) [1] "expression" Calling eval() invokes many behaviours, some are not immediately obvious: > class(eval(parse(text="5+5"))) [1] "numeric" > class(eval(parse(text="gray"))) [1] "function" > class(eval(parse(text="blue"))) Error in eva...

I haven't used regular expressions at all, so I'm having difficulty troubleshooting. I want the regex to match only when the contained string is all numbers; but with the two examples below it is matching a string that contains all numbers plus an equals sign like "1234=4321". I'm sure there's a way...

... In CSS3, you can use the :not() filter, but not all browsers fully support CSS3 yet, so be sure you know what you're doing which is now supported by all major browsers (and has been for quite some time; this is an old answer...). Example: <input type="text" value="wi...

...places : Enum Types, from The Java Tutorials The compiler automatically adds some special methods when it creates an enum. For example, they have a static values method that returns an array containing all of the values of the enum in the order they are declared. This method is commonl...

...asy to implement an O(n) shuffle. The code in the question "works" by basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number. I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements. Implementing a simple S...

... The solution to this is actually very easy, but not at all obvious. You have to trigger something called a "block formatting context" (BFC), which interacts with floats in a specific way. Just take that second div, remove the float, and give it overfl...

...rted off with me not being able to log in as root any more on my mysql install. I was attempting to run mysql without passwords turned on... but whenever I ran the command ...

...uble check this, though as I haven't verified this recently. Per default, all reflogs are activated for non-bare repositories: [core] logAllRefUpdates = true share | improve this answer ...

...hat is the idiomatic way of doing this for a subset of columns (instead of all of them)? I've defined a character vector convcols of columns. dt[,lapply(.SD,as.numeric),.SDcols=convcols] is almost instant while dt[,convcols:=lapply(.SD,as.numeric),.SDcols=convcols] almost freezes up R, so I'm guessi...

... is an alias for the open() built-in. So io.open() works in Python 2.6 and all later versions, including Python 3.4. See docs: http://docs.python.org/3.4/library/io.html Now, for the original question: when reading text (including "plain text", HTML, XML and JSON) in Python 2 you should always use ...