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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 replace a hash key with another key
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At last! This is exactly what I searched!
– TiSer
Sep 30 '16 at 8:23
4
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enum - getting value of enum on string conversion
...bject. Use the .value attribute if you wanted just to print that:
print(D.x.value)
See the Programmatic access to enumeration members and their attributes section:
If you have an enum member and need its name or value:
>>>
>>> member = Color.red
>>> member.name
're...
Omit rows containing specific column of NA
...ete.cases function and put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data[completeVec, ])
}
completeFun(DF, "y")
# x y z
# 1...
How to join (merge) data frames (inner, outer, left, right)
...its optional parameters:
Inner join: merge(df1, df2) will work for these examples because R automatically joins the frames by common variable names, but you would most likely want to specify merge(df1, df2, by = "CustomerId") to make sure that you were matching on only the fields you desired. You ...
Extract subset of key-value pairs from Python dictionary object?
...u're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
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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...
How can I convert my device token (NSData) into an NSString?
...iceToken: Data) {
let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
print(token)
}
Old answer using NSData:
func application(application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: NSData) {
let tokenChars = UnsafePointer<CChar&...
Does Python optimize tail recursion?
...ng to transform it like that - just: from operator import add; reduce(add, xrange(n + 1), csum) ?
– Jon Clements♦
Nov 27 '12 at 20:10
38
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Most efficient method to groupby on an array of objects
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