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Convert column classes in data.table
...rter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(....
bash: pip: command not found
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531
Why not just do sudo easy_install pip or if this is for python 2.6 sudo easy_install-2.6 pip?
...
Maven error: Could not find or load main class org.codehaus.plexus.classworlds.launcher.Launcher
I have installed a latest maven-3.0.4 on Windows 7 :
The installation details are as follows:
Installation Path :
...
How do I get a list of all the duplicate items using pandas in python?
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173
Method #1: print all rows where the ID is one of the IDs in duplicated:
>>> import pan...
How to convert list of key-value tuples into dictionary?
...injagecko
72.5k2121 gold badges124124 silver badges134134 bronze badges
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Preserving signatures of decorated functions
...))
return f(*args, **kwargs)
@args_as_ints
def funny_function(x, y, z=3):
"""Computes x*y + 2*z"""
return x*y + 2*z
print funny_function("3", 4.0, z="5")
# 22
help(funny_function)
# Help on function funny_function in module __main__:
#
# funny_function(x, y, z=3)
# Computes x*y + ...
jQuery map vs. each
...you can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. F...
汇编语言（王爽著）附书签 - 文档下载 - 清泛网 - 专注C/C++及内核技术
...自己学，看了很多书，国内像这样的好书真的是很难得。3、更珍贵的是老师的编排，可以说比国外的还好（当然从知识点来说不如国外的书，但是这是一本入门书）
我的感想：1、计算机科学方面的好书，中国基本上没有（运...
How to return dictionary keys as a list in Python?
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answered May 29 '13 at 16:25
Chris Chris
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