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OS X: equivalent of Linux's wget
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edited Sep 3 '17 at 20:05
Mark Amery
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an...
DISTINCT for only one column
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If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTI...
Get type of all variables
...character
typeof(3 + 四) #R pukes on unicode error
typeof(iconv("a", "latin1", "UTF-8")) #UTF-8 characters character
typeof(5 == 5) #result of a comparison: logical
How to get the class of a variable you have in R
The R function class ...
How to find common elements from multiple vectors?
....
– Montgomery Clift
Oct 3 '19 at 8:05
add a comment
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Programmatically retrieve memory usage on iPhone
...iB): %f", ((CGFloat)info.resident_size / 1048576));
} else {
NSLog(@"Error with task_info(): %s", mach_error_string(kerr));
}
}
There is also a field in the structure info.virtual_size which will give you the number of bytes available virtual memory (or memory allocated to your application...
Select unique or distinct values from a list in UNIX shell script
...s too.
– Mingye Wang
Dec 9 '15 at 5:05
I figured out that uniq seams to process only adjacent lines (at least by defau...
Search for executable files using find command
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Error find: invalid mode ‘+111’ on findutils 4.5.11 4.fc20.
– sourcejedi
Jul 17 '14 at 10:31
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Find index of last occurrence of a substring in a string
... recent call last):
File "<stdin>", line 1, in <module>
ValueError: substring not found
The difference is when the substring is not found, rfind() returns -1 while rindex() raises an exception ValueError (Python2 link: ValueError).
If you do not want to check the rfind() return cod...
Understanding the map function
...your function should look for None and handle them, otherwise you will get errors. In Python 3 map() will stop after finishing with the shortest list. Also, in Python 3, map() returns an iterator, not a list.
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Are there pronounceable names for common Haskell operators? [closed]
... too.
– user824425
Oct 12 '11 at 23:05
1
@Tinctorius, whether composition is after or before depe...