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How to detect the physical connected state of a network cable/connector?
In a Linux environment, I need to detect the physical connected or disconnected state of an RJ45 connector to its socket. Preferably using BASH scripting only.
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SQL server query to get the list of columns in a table along with Data types, NOT NULL, and PRIMARY
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To avoid duplicate rows for some columns, use user_type_id instead of system_type_id.
SELECT
c.name 'Column Name',
t.Name 'Data type',
c.max_length 'Max Length',
c.precision ,
c.scale ,
c.is_nullable,
ISNULL(i.is_primary_key,...
Repeat each row of data.frame the number of times specified in a column
...s the simplest way to expand each row the first two columns of the data.frame above, so that each row is repeated the number of times specified in the column 'freq'?
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Changing the current working directory in Java?
... don't think i've found a single difference between java and c# that makes me think, "those java guys sure know what they're doing"
– Jake
Feb 22 '12 at 21:05
2
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Working with huge files in VIM
...I had a 12GB file to edit today. The vim LargeFile plugin did not work for me. It still used up all my memory and then printed an error message :-(. I could not use hexedit for either, as it cannot insert anything, just overwrite. Here is an alternative approach:
You split the file, edit the parts ...
Changing the default header comment license in Xcode
Whenever I create a new .cpp/.h file in Xcode a comment is added to the top of the file. For example:
11 Answers
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ValueError: setting an array element with a sequence
...are trying to create an array from a list that isn't shaped like a multi-dimensional array. For example
numpy.array([[1,2], [2, 3, 4]])
or
numpy.array([[1,2], [2, [3, 4]]])
will yield this error message, because the shape of the input list isn't a (generalised) "box" that can be turned into a...
How to do exponentiation in clojure?
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Clojure.contrib.math is now deprecated, see Math.Numeric-Tower
– alvaro g
Mar 14 '16 at 17:23
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What is the difference between & and && in Java?
...se since the result will be false
(x != 0) & (1/x > 1) <-- this means evaluate (x != 0) then evaluate (1/x > 1) then do the &. the problem is that for x=0 this will throw an exception.
(x != 0) && (1/x > 1) <-- this means evaluate (x != 0) and only if this is true th...
Can Rails Routing Helpers (i.e. mymodel_path(model)) be Used in Models?
...d Thing. Thing has a url attribute that can optionally be set to a URL somewhere on the Internet. In view code, I need logic that does the following:
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