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Omit rows containing specific column of NA
...ses 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 1 0 ...
Dynamically creating keys in a JavaScript associative array
...
144
Use the first example. If the key doesn't exist it will be added.
var a = new Array();
a['na...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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31
Since 3.24.0 SQLite also supports upsert, so now you can simply write the following
INSERT INTO...
How to convert CharSequence to String?
...
answered Oct 10 '11 at 0:38
Mike SamuelMike Samuel
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How to convert a Drawable to a Bitmap?
...s accept Bitmap s only. I cannot use WallpaperManager because I'm pre 2.1.
20 Answers
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Why do results vary based on curly brace placement?
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169
That's one of the pitfalls of JavaScript: automatic semicolon insertion. Lines that do not end...
Full examples of using pySerial package [closed]
...he device you are connecting to)
ser = serial.Serial(
port='/dev/ttyUSB1',
baudrate=9600,
parity=serial.PARITY_ODD,
stopbits=serial.STOPBITS_TWO,
bytesize=serial.SEVENBITS
)
ser.isOpen()
print 'Enter your commands below.\r\nInsert "exit" to leave the application.'
input=1
whil...
Which, if any, C++ compilers do tail-recursion optimization?
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131
All current mainstream compilers perform tail call optimisation fairly well (and have done for...