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How to use NULL or empty string in SQL
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answered Mar 27 '13 at 15:55
codingbadgercodingbadger
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What is WEB-INF used for in a Java EE web application?
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edited May 15 '17 at 5:34
Basil Bourque
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What is Weak Head Normal Form?
...re not in normal form:
1 + 2 -- we could evaluate this to 3
(\x -> x + 1) 2 -- we could apply the function
"he" ++ "llo" -- we could apply the (++)
(1 + 1, 2 + 2) -- we could evaluate 1 + 1 and 2 + 2
Weak head normal form
An expression in weak head normal ...
Get JSF managed bean by name in any Servlet related class
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263
In a servlet based artifact, such as @WebServlet, @WebFilter and @WebListener, you can grab a "p...
How to fetch the row count for all tables in a SQL SERVER database [duplicate]
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13 Answers
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How do I debug error ECONNRESET in Node.js?
...ity wiki
2 revs, 2 users 67%Suzana_K
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How to find all duplicate from a List? [duplicate]
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213
In .NET framework 3.5 and above you can use Enumerable.GroupBy which returns an enumerable of en...
How to convert local time string to UTC?
...e code, using local timezone "America/Los_Angeles", for the string "2001-2-3 10:11:12":
import pytz, datetime
local = pytz.timezone ("America/Los_Angeles")
naive = datetime.datetime.strptime ("2001-2-3 10:11:12", "%Y-%m-%d %H:%M:%S")
local_dt = local.localize(naive, is_dst=None)
utc_dt = local_dt.a...
How to install the Raspberry Pi cross compiler on my Linux host machine?
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I'm gonn...
Apply a function to every row of a matrix or a data frame
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You simply use the apply() function:
R> M <- matrix(1:6, nrow=3, byrow=TRUE)
R> M
[,1] [,2]
[1,] 1 2
[2,] 3 4
[3,] 5 6
R> apply(M, 1, function(x) 2*x[1]+x[2])
[1] 4 10 16
R>
This takes a matrix and applies a (silly) function to each row. You pass extr...