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Group by multiple columns in dplyr, using string vector input
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data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>%...
What characters are valid for JavaScript variable names?
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1000
+50
To quot...
Using [UIColor colorWithRed:green:blue:alpha:] doesn't work with UITableView seperatorColor?
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You need to divide by 255.0
Because I hardly ever use values between 1.0 and 0.0, I created a very simple UIColor category that does the messy looking division by itself: (from http://github.com/Jon889/JPGeneral)
//.h file
@interface UIColor (JPExtr...
Draw in Canvas by finger, Android
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+200
Start By going through the Fingerpaint demo in the sdk sample.
Another Sample:
public class MainActivity extends Activity {
D...
PHP: Count a stdClass object
...urn the right number when I run the count($obj) function. The object has 30 properties, but the return on the count() function is say 1.
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Replacing column values in a pandas DataFrame
... something like this:
w['female'] = w['female'].map({'female': 1, 'male': 0})
(Here I convert the values to numbers instead of strings containing numbers. You can convert them to "1" and "0", if you really want, but I'm not sure why you'd want that.)
The reason your code doesn't work is because...
Generating random numbers in Objective-C
...a head mainly, and I want a way to generate a pseudo-random number between 0 and 74. In Java I would use the method:
13 Ans...
How to create a cron job using Bash automatically without the interactive editor?
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20 Answers
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Mercurial move changes to a new branch
...e extension. Suppose you have a history like this:
@ changeset: 2:81b92083cb1d
| tag: tip
| summary: my new feature: edit file a
|
o changeset: 1:8bdc4508ac7b
| summary: my new feature: add file b
|
o changeset: 0:d554afd54164
summary: initial
This means, revisi...
How to create circle with Bézier curves?
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10 Answers
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