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Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with i...
Does .NET provide an easy way convert bytes to KB, MB, GB, etc.?
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197
Here is a fairly concise way to do this:
static readonly string[] SizeSuffixes =
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Reverse Range in Swift
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185
Update For latest Swift 3 (still works in Swift 4)
You can use the reversed() method on a ran...
How do you make an array of structs in C?
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107
#include<stdio.h>
#define n 3
struct body
{
double p[3];//position
double v[3];/...
Fastest way to flatten / un-flatten nested JSON objects
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13 Answers
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How to insert element into arrays at specific position?
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214
array_slice() can be used to extract parts of the array, and the union array operator (+) can r...
How to determine the longest increasing subsequence using dynamic programming?
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19 Answers
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How to put the legend out of the plot
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17 Answers
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How to map atan2() to degrees 0-360
atan2(y, x) has that discontinuity at 180° where it switches to -180°..0° going clockwise.
15 Answers
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What is IP address '::1'?
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152
::1 is the loopback address in IPv6. Think of it as the IPv6 version of 127.0.0.1.
See http:...