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MySQL - length() vs char_length()
...() returns the length of the string measured in characters.
This is especially relevant for Unicode, in which most characters are encoded in two bytes. Or UTF-8, where the number of bytes varies. For example:
select length(_utf8 '€'), char_length(_utf8 '€')
--> 3, 1
As you can see the E...
ggplot2 keep unused levels barplot
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You need to set drop=FALSE on both scales (fill and x) like this:
library(ggplot2)
df <- data.frame(type=c("A", "A", "A", "B", "B"), group=rep("group1", 5))
df1 <- data.frame(type=c("A", "A", "A", "B", "B", "A", "A", "C", "B", "B"), group=c(rep("group1", 5),rep("group2"...
How to launch Safari and open URL from iOS app
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@g_fred. Why would he not be able to include a Swift version?
– ericgu
Mar 24 '15 at 13:21
2
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Conditionally Remove Dataframe Rows with R [duplicate]
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Actually, a simpler way of viewing it is: foo.isolated <- subset(foo, !(sid == "sid104" & game.num == 7))
– WGray
Aug 6 '15 at 21:01
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What is the inverse function of zip in python? [duplicate]
...ion from the numpy library to sort tuples and now I have a list containing all the tuples. I had since modified that list and now I would like to restore the tuples so I can use my data. How can I do this?
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Is it possible to have a multi-line comments in R? [duplicate]
...u can only use such blocks in places where an expression would be syntactically valid - no commenting out parts of lists, say.
Regarding what do in which IDE: I'm a Vim user, and I find
NERD Commenter an utterly excellent tool for quickly commenting or uncommenting multiple lines. Very user-friendl...
omp parallel vs. omp parallel for
...xact implementation might deal with them differently.
The combined parallel worksharing constructs are a shortcut for
specifying a parallel construct containing one worksharing construct
and no other statements. Permitted clauses are the union of the clauses
allowed for the parallel and w...
How to select a radio button by default? [duplicate]
...gt;
Please note, that the actual value of checked attribute does not actually matter; it's just a convention to assign "checked". Most importantly, strings like "true" or "false" don't have any special meaning.
If you don't aim for XHTML conformance, you can simplify the code to:
<input type=...
Math - mapping numbers
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If your number X falls between A and B, and you would like Y to fall between C and D, you can apply the following linear transform:
Y = (X-A)/(B-A) * (D-C) + C
That should give you what you want, although your question is a little ambigu...
Node.js/Windows error: ENOENT, stat 'C:\Users\RT\AppData\Roaming\npm'
I have Windows 7 32-bit. I installed the latest Node.js 32 bit.
When I try to run the command npm install jquery , I receive the error:
...