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Ruby Hash to array of values
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265
Also, a bit simpler....
>> hash = { "a"=>["a", "b", "c"], "b"=>["b", "c"] }
=> {...
Scala: what is the best way to append an element to an Array?
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stefanobaghino
7,94333 gold badges2525 silver badges4848 bronze badges
answered Sep 21 '11 at 12:57
tenshitenshi
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How do I get SUM function in MySQL to return '0' if no values are found?
...e it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE foo
(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,...
Remove duplicated rows using dplyr
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edited Jun 19 '18 at 12:57
Axeman
25.5k66 gold badges6363 silver badges7171 bronze badges
answered Apr...
Regex to replace everything except numbers and a decimal point
...parseFloat. That will remove additional decimal points. e.g. parseFloat("46554.4655465.54654.545345.5") = 46554.4655465
– Simon
Dec 6 '16 at 3:57
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What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...lues,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e'}
Speed comparion (using Wouter's method)
In [6]: df = pd.DataFrame(randint(0,10,10000).reshape(5000,2),columns=list('AB'))
In [7]: %timeit dict(zip(df.A,df.B))
1000 loops, best of 3: 1.27 ms per loop
In [8]: %time...
std::vector performance regression when enabling C++11
...0 ./a.out
Performance counter stats for './a.out' (10 runs):
35.426793 task-clock # 0.986 CPUs utilized ( +- 1.75% )
4 context-switches # 0.116 K/sec ( +- 5.69% )
0 CPU-migrations ...
How can I brew link a specific version?
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