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SQL query return data from multiple tables
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472
Part 1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an in...
Element-wise addition of 2 lists?
...t;>> from operator import add
>>> list( map(add, list1, list2) )
[5, 7, 9]
or zip with a list comprehension:
>>> [sum(x) for x in zip(list1, list2)]
[5, 7, 9]
Timing comparisons:
>>> list2 = [4, 5, 6]*10**5
>>> list1 = [1, 2, 3]*10**5
>>> %tim...
Explain the use of a bit vector for determining if all characters are unique
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12 Answers
12
Active
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What is the difference between Python's list methods append and extend?
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20 Answers
20
Active
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Counting the number of elements with the values of x in a vector
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521
You can just use table():
> a <- table(numbers)
> a
numbers
4 5 23 34 43 54 ...
Linux下安装项目管理工具Redmine - 开源 & Github - 清泛网 - 专注C/C++及内核技术
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保存退出:wq
# . .bash_profile
2、RubyGems安装
# wget http://rubyforge.org/frs/download.php/60718/rubygems-1.3.5.tgz
# tar zxvf rubygems-1.3.5.tgz
# cd rubygems-1.3.5
# ruby setup.rb
3、Rake安装
# gem install ra...
Deep copy of a dict in python
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502
How about:
import copy
d = { ... }
d2 = copy.deepcopy(d)
Python 2 or 3:
Python 3.2 (r32:8844...
How can I plot separate Pandas DataFrames as subplots?
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264
You can manually create the subplots with matplotlib, and then plot the dataframes on a specif...
How do I sort one vector based on values of another
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answered Oct 14 '09 at 21:47
Ian FellowsIan Fellows
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