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get list of pandas dataframe columns based on data type

...object dtype: object In [13]: msk = df.dtypes == np.float64 # or object, etc. In [14]: msk Out[14]: 0 False 1 True 2 False dtype: bool You can look at just those columns with the desired dtype: In [15]: df.loc[:, msk] Out[15]: 1 0 2.3456 Now you can use round (or whateve...
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How to sum a variable by group

... Is there anyway of maintaining an ID column? Say the categories are ordered and the ID column is 1:nrow(df), is it possible to keep the starting position of each category after aggregating? So the ID column would end up as, for example, 1, 3, 4, 7 after collapsing with aggregate. In my case ...
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get all keys set in memcached

... will asynchronously dump as many keys as you want. you'll get them out of order but it hits all LRU's, and unless you're deleting/replacing items multiple runs should yield the same results. Source: GH-405. Related: List all objects in memcached Writing a Redis client in pure bash (it's Redis, b...
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Python append() vs. + operator on lists, why do these give different results?

...st. Specifically, it appends each of the elements of sequence in iteration order. An aside Being an operator, + returns the result of the expression as a new value. Being a non-chaining mutator method, list.extend() modifies the subject list in-place and returns nothing. Arrays I've added this due t...
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Comparing HTTP and FTP for transferring files

... Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity. ...
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Can't update Macports (with Mac OS X Mavericks)

...oceeding despite dependencies. on each one. Luckily i made a copy of the etc and apache2/conf dirs, so should be able to get my config back when it eventually finishes... after 30 minutes or so it threw an error Unable to open port: extra characters after close-quote So i did self update again ...
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How do I add a margin between bootstrap columns without wrapping [duplicate]

...0.2) 0%, rgba(125, 185, 232, 0) 100%); background-repeat: repeat; border-radius:10px; padding: 5px; } share | improve this answer | follow | ...
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Signed versus Unsigned Integers

... little vs. big endian has to do with the order of the bytes on the platform. Little endian might do 0xFF 0xFE 0x7F while big endian will do 0x7F 0xFE 0xFF. – Jasper Bekkers Oct 29 '08 at 18:35 ...
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Expert R users, what's in your .Rprofile? [closed]

...l, NAs generated Factors are great when you need them (e.g. implementing ordering in graphs) but a nuisance most of the time. share | improve this answer | follow ...
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Circular dependency in Spring

...ences is that bean injection / property setting might occur in a different order to what your XML wiring files would seem to imply. So you need to be careful that your property setters don't do initialization that relies on other setters already having been called. The way to deal with this is to ...