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Can modules have properties the same way that objects can?
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edited Mar 31 '19 at 9:48
mari.mts
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answered May 19 '09 at 1:09
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How do you use “
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function(x) x ^ exponent
}
square <- power(2)
square(2) # -> [1] 4
square(4) # -> [1] 16
cube <- power(3)
cube(2) # -> [1] 8
cube(4) # -> [1] 64
The ability to manage variables at two levels also makes it possible to maintain the state across function invocations by allowing...
How to remove duplicate values from a multi-dimensional array in PHP
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647
Here is another way. No intermediate variables are saved.
We used this to de-duplicate result...
PHP Sort a multidimensional array by element containing date
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answered May 26 '10 at 6:44
Ferdinand BeyerFerdinand Beyer
55.1k1212 gold badges136136 silver badges138138 bronze badges
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What's the best way of implementing a thread-safe Dictionary?
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43
As Peter said, you can encapsulate all of the thread safety inside the class. You will need to...
Sorting a Python list by two fields
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edited Sep 4 '15 at 8:54
BrechtDeMan
5,52433 gold badges2121 silver badges2424 bronze badges
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How can I get the active screen dimensions?
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144
Screen.FromControl, Screen.FromPoint and Screen.FromRectangle should help you with this. For ex...
Primary key or Unique index?
...1 (foo, bar) VALUES (3, 1); -- OK
INSERT INTO table1 (foo, bar) VALUES (1, 4); -- Fails!
Duplicate entry '1' for key 'ux_table1_foo'
The last insert fails because it violates the unique index on column foo when it tries to insert the value 1 into this column for a second time.
In MySQL a unique ...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...le:
In [7]: df
Out[7]:
0 1
0 NaN NaN
1 -0.494375 0.570994
2 NaN NaN
3 1.876360 -0.229738
4 NaN NaN
In [8]: df.fillna(0)
Out[8]:
0 1
0 0.000000 0.000000
1 -0.494375 0.570994
2 0.000000 0.000000
3 1.876360 -0.229738
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Best way to simulate “group by” from bash?
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