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How to Correctly Use Lists in R?
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Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different ...
'printf' vs. 'cout' in C++
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360
I'm surprised that everyone in this question claims that std::cout is way better than printf, ...
How do I capture the output of a script if it is being ran by the task scheduler?
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edited Sep 3 '13 at 23:50
Igor
29.8k1414 gold badges6666 silver badges106106 bronze badges
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get list of pandas dataframe columns based on data type
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320
If you want a list of columns of a certain type, you can use groupby:
>>> df = pd.Da...
How to determine if one array contains all elements of another array
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313
a = [5, 1, 6, 14, 2, 8]
b = [2, 6, 15]
a - b
=> [5, 1, 14, 8]
b - a
=> [15]
(b - a).e...
Convert char to int in C and C++
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lucidbrot
3,11022 gold badges2424 silver badges4848 bronze badges
answered Feb 17 '11 at 14:16
Foo BahFoo Bah
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On Duplicate Key Update same as insert
...ernatively, you can use:
INSERT INTO table (id,a,b,c,d,e,f,g)
VALUES (1,2,3,4,5,6,7,8)
ON DUPLICATE KEY
UPDATE a=a, b=b, c=c, d=d, e=e, f=f, g=g;
To get the id from LAST_INSERT_ID; you need to specify the backend app you're using for the same.
For LuaSQL, a conn:getlastautoid() fetches the ...
__FILE__, __LINE__, and __FUNCTION__ usage in C++
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edited Mar 13 '17 at 13:15
answered Feb 27 '09 at 23:28
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Python group by
...Do it in 2 steps. First, create a dictionary.
>>> input = [('11013331', 'KAT'), ('9085267', 'NOT'), ('5238761', 'ETH'), ('5349618', 'ETH'), ('11788544', 'NOT'), ('962142', 'ETH'), ('7795297', 'ETH'), ('7341464', 'ETH'), ('9843236', 'KAT'), ('5594916', 'ETH'), ('1550003', 'ETH')]
>>&g...