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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
Split string into an array in Bash
In a Bash script I would like to split a line into pieces and store them in an array.
22 Answers
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Xcode duplicate/delete line
Coming from Eclipse and having been used to duplicate lines all the time, it's pretty strange finding out that Xcode has no such function. Or does it?
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What is a Y-combinator? [closed]
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@Andre MacFie: I didn't comment on the effort, I commented on the quality. In general, the policy on Stack Overflow is that answers should be self contained, with links to more information.
– Jørgen Fogh...
Need for predictable random generator
I'm a web-game developer and I got a problem with random numbers. Let's say that a player has 20% chance to get a critical hit with his sword. That means, 1 out of 5 hits should be critical. The problem is I got very bad real life results — sometimes players get 3 crits in 5 hits, sometimes none i...
Does anyone still use [goto] in C# and if so why? [closed]
I was wondering whether anyone still uses the "goto" keyword syntax in C# and what possible reasons there are for doing so.
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Generate random password string with requirements in javascript
I want to generate a random string that has to have 5 letters from a-z and 3 numbers.
18 Answers
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Reorder levels of a factor without changing order of values
I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be.
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How to search and replace globally, starting from the cursor position and wrapping around the end of
When I search with the / Normal-mode command:
6 Answers
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image processing to improve tesseract OCR accuracy
...o convert documents into text. The quality of the documents ranges wildly, and I'm looking for tips on what sort of image processing might improve the results. I've noticed that text that is highly pixellated - for example that generated by fax machines - is especially difficult for tesseract to pr...