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filter for complete cases in data.frame using dplyr (case-wise deletion)
...data.frame for complete cases using dplyr? complete.cases with a list of all variables works, of course. But that is a) verbose when there are a lot of variables and b) impossible when the variable names are not known (e.g. in a function that processes any data.frame).
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What does `unsigned` in MySQL mean and when to use it?
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MySQL says:
All integer types can have an optional
(nonstandard) attribute UNSIGNED.
Unsigned type can be used to permit
only nonnegative numbers in a column
or when you need a larger upper
numeric range for the column. For
e...
How to send HTML-formatted email? [duplicate]
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Setting isBodyHtml to true allows you to use HTML tags in the message body:
msg = new MailMessage("xxxx@gmail.com",
"yyyy@gmail.com", "Message from PSSP System",
"This email sent by the PSSP system<br />" +
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Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
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How to track child process using strace?
...ously search for the parent thread, then the grandparent thread, and so on all the way to the root process.
4 Answers
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How to mock the Request on Controller in ASP.Net MVC?
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Your link doesn't work, but the following seems to work _request.Setup(o => o.Form).Returns(new NameValueCollection());
– Vdex
May 31 '12 at 11:26
add a ...
How do you get the index of the current iteration of a foreach loop?
...or iterating over collections that implement IEnumerable. It does this by calling GetEnumerator on the collection, which will return an Enumerator.
This Enumerator has a method and a property:
MoveNext()
Current
Current returns the object that Enumerator is currently on, MoveNext updates Current t...
HTML table td meaning
...ered Sep 20 '15 at 22:27
Dbeast1_16Dbeast1_16
5
1
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What's the difference between MyISAM and InnoDB? [duplicate]
...es made by two or more DML operations handled as single unit of work, with all of the changes either applied, or all the changes reverted) then you would choose the InnoDB engine, since these features are absent from the MyISAM engine.
Those are the two biggest differences. Another big difference is...
LINQ equivalent of foreach for IEnumerable
...Multi-threading, possible by PLINQ. 2. Exceptions, you may want to collect all exception in the loop and throw it at once; and they are noise codes.
– Dennis C
Feb 7 '10 at 7:06
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