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Omit rows containing specific column of NA
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You could use the complete.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...
Hidden Features of JavaScript? [closed]
...ay -- it's just an object. So you can't do join(), pop(), push(), slice() and so forth. (You can convert it to a real array if you want: "var argArray = Array.prototype.slice.call(arguments);" )
– Jacob Mattison
Jan 26 '09 at 21:37
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Remove duplicated rows using dplyr
...mple(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data frame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need...
What is Scala's yield?
I understand Ruby and Python's yield. What does Scala's yield do?
9 Answers
9
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Why use softmax as opposed to standard normalization?
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There is one nice attribute of Softmax as compared with standard normalisation.
It react to low stimulation (think blurry image) of your neural net with rather uniform distribution and to high stimulation (ie. large numbers, think crisp image) with probabilities close to 0 and 1.
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multiple packages in context:component-scan, spring config
...@elcadro must've been through other reasons, since this is well documented and advertised feature
– eis
Nov 23 '13 at 7:55
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Reset keys of array elements in php?
...es($ret); is enough to reset numeric keys
– Marek Lewandowski
May 7 '13 at 8:24
2
I dont know if ...
How to check if a variable is set in Bash?
...ar+x} is a parameter expansion which evaluates to nothing if var is unset, and substitutes the string x otherwise.
Quotes Digression
Quotes can be omitted (so we can say ${var+x} instead of "${var+x}") because this syntax & usage guarantees this will only expand to something that does not requ...
Assign pandas dataframe column dtypes
...you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x ...
Can't use modulus on doubles?
...rogram in C++ (compiled using g++). I'm trying to apply two doubles as operands to the modulus function, but I get the following error:
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