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Order data frame rows according to vector with specific order
...atch data. One possible try for this
left_join(data.frame(name=target),df,by="name")
Note that the input for ***_join require tbls or data.frame
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ImportError: Cannot import name X
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@user2032433 That really depends on what you mean by 'know each other'. It is true that good design usually produces a tree of one-way dependencies and this is normally the best approach. But there are exceptions to this. C++ classes certainly can refer to one another circul...
Extracting numbers from vectors of strings
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How about
# pattern is by finding a set of numbers in the start and capturing them
as.numeric(gsub("([0-9]+).*$", "\\1", years))
or
# pattern is to just remove _years_old
as.numeric(gsub(" years old", "", years))
or
# split by space, get the ...
How to write a multidimensional array to a text file?
...savetxt chokes on ndarrays with more than 2 dimensions... This is probably by design, as there's no inherently defined way to indicate additional dimensions in a text file.
E.g. This (a 2D array) works fine
import numpy as np
x = np.arange(20).reshape((4,5))
np.savetxt('test.txt', x)
While the same...
How is the 'use strict' statement interpreted in Node.js? [duplicate]
...code is nothing but your JavaScript code. All Node.js code are interpreted by the V8 JavaScript engine. The V8 JavaScript Engine is an open source JavaScript engine developed by Google for Chrome web browser.
So, there will be no major difference how "use strict"; is interpreted by the Chrome brows...
Java : How to determine the correct charset encoding of a stream
...ed character set. UniversalDetector ud = new UniversalDetector(null); byte[] bytes = FileUtils.readFileToByteArray(new File(file)); ud.handleData(bytes, 0, bytes.length); ud.dataEnd(); detectedCharset = ud.getDetectedCharset();
– Rohit Verma
Sep 1...
How to make an immutable object in Python?
...that when you pass them as a parameter through a function, they are copied by value, rather than another reference being made. Would namedtuples be copied by value when passed through functions?
– hlin117
Oct 11 '15 at 17:46
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Escape double quotes in parameter
... OS where globbing, shell expansion, and parameter unescaping is performed by the executable being invoked instead of the shell. You never know which convention, if any, the invoked executable honours.
– binki
Mar 28 '14 at 2:15
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How to update bower.json with installed packages?
... The dependencies that not has declared in bower.json are identified by "extraneous" tag on console.
– otaviodecampos
Jan 18 '18 at 13:52
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Is there a standardized method to swap two variables in Python?
...ments is created in the memory. The two element are the objects designated by the identifiers b and a, that were existing before the instruction is encoutered during an execution of program
just after the creation of this tuple, no assignement of this tuple object have still been made, but it doesn'...