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Applying a function to every row of a table using dplyr?

...f Hadley's examples using pmap: iris %>% mutate(Max.Len= purrr::pmap_dbl(list(Sepal.Length, Petal.Length), max)) Using this approach, you can give an arbitrary number of arguments to the function (.f) inside pmap. pmap is a good conceptual approach because it reflects the fact that when ...
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Pandas aggregate count distinct

... How about either of: >>> df date duration user_id 0 2013-04-01 30 0001 1 2013-04-01 15 0001 2 2013-04-01 20 0002 3 2013-04-02 15 0002 4 2013-04-02 30 0002 >>> df.groupby("date").agg({"duration": np.sum, "use...
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Python: using a recursive algorithm as a generator

...],string[:i]+string[i+1:] pairs. Then it would be: for letter,rest in first_letter_options(string): for perm in getPermuations(rest): yield letter+perm – Thomas Andrews Oct 14 '16 at 19:04 ...
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Map and Reduce in .NET

...nge(1, 10).Where(x => x % 2 == 0); https://www.justinshield.com/2011/06/mapreduce-in-c/ share | improve this answer | follow | ...
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Can a shell script set environment variables of the calling shell? [duplicate]

... answered Jan 30 '09 at 19:06 converter42converter42 6,73122 gold badges2525 silver badges2323 bronze badges ...
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What is the difference between null and undefined in JavaScript?

...d. – Muhammad Umer Aug 10 '13 at 11:06  |  show 11 more comments ...
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String.Replace ignoring case

...) – Oleg Zarevennyi Mar 1 '18 at 20:06 2 Interesting approach. Probably the better one (better th...
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Why can't yield return appear inside a try block with a catch?

...ck"); } Console.WriteLine("Post"); into (sort of pseudo-code): case just_before_try_state: try { Console.WriteLine("a"); } catch (Something e) { CatchBlock(); goto case post; } __current = 10; return true; case just_after_yield_return: ...
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Resharper- Find all unused classes

...hing like the following : public class IoC { private WindsorContainer _container; private IoC() { _container = new WindsorContainer(); } public static void RegisterFromAssembly(Assembly assembly, string classEndsWith, LifeTime lifeTime) { var lifestyle = C...
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Generating a random password in php

...assword using rand is a really bad idea. It's not a secure PRNG. (and no mt_rand isn't better either) – CodesInChaos Oct 31 '13 at 16:56 19 ...