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Adding a column to a data.frame
...xt, [[.data.frame.
Data frames can be indexed in several modes. When [ and [[ are used with a single vector index (x[i] or x[[i]]), they index the data frame as if it were a list.
my.dataframe["new.col"] <- a.vector
my.dataframe[["new.col"]] <- a.vector
The data.frame method for $, ...
What's the best name for a non-mutating “add” method on an immutable collection?
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Unless I'm missing it, System.Linq.Enumerable (and Linq in general) only uses Concat() for "sequence + sequence", never "item + sequence". The problem that someone "might expect it to add two lists together rather than adding a single value to the other list" was explici...
Double vs. BigDecimal?
I have to calculate some floating point variables and my colleague suggest me to use BigDecimal instead of double since it will be more precise. But I want to know what it is and how to make most out of BigDecimal ?
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Google Play app description formatting
I've made an Android application that is available on Google Play. Now I want to add some more formatting to my app description (eg. indent, links, lists..). But I cannot find any website where possible formatting is listed. Google Help pages cannot help me either on this subject. There exists a lot...
What are the best Haskell libraries to operationalize a program? [closed]
...ogram to do in order to consider it "operationalized" – that is, running and maintainable in a measurable and verifiable way by both engineers and operations staff. For my purposes, an operationalized program must:
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Prevent browser from loading a drag-and-dropped file
I'm adding an html5 drag and drop uploader to my page.
10 Answers
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Config Error: This configuration section cannot be used at this path
...ents over the years have certified this works all the way up to Windows 10 and Server 2019, as well.
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Eclipse Kepler for OS X Mavericks request Java SE 6
I have just made a clean installation of OS X Mavericks , and I have downloaded Eclipse Kepler , but if I execute it, gives me this message:
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Nginx reverse proxy causing 504 Gateway Timeout
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@Dax Fohl: That's curious. I pulled down the source and had a quick look and from what I can see, setting any proxy_ setting aside from the proxy_pass will initialize a bunch of settings which I presume will run the proxy in a different way so maybe setting anything will give ...
Memoization in Haskell?
...f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate results.
But it still takes linear time just to index to find the memoized answer for mf. This means that results like:
*Main Dat...