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Paste multiple columns together
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# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed together
data$x <- apply( d...
Return multiple values in JavaScript?
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1380
No, but you could return an array containing your values:
function getValues() {
return [...
Javascript and regex: split string and keep the separator
...1
JonJon
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How to change the order of DataFrame columns?
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34 Answers
34
Active
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rails 3 validation on uniqueness on multiple attributes
I use Rails 3.0.0.beta4
3 Answers
3
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Difference between map, applymap and apply methods in Pandas
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Straight from Wes McKinney's Python for Data Analysis book, pg. 132 (I highly recommended this book):
Another frequent operation is applying a function on 1D arrays to each column or row. DataFrame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3),...
Why is address zero used for the null pointer?
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edited May 3 '10 at 17:44
answered May 3 '10 at 17:22
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JavaScript function similar to Python range()
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23 Answers
23
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Pass a variable into a partial, rails 3?
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237
Try this:
<% @posts.each do |post| %>
<%= render 'middle', :post => post %>
&...
Converting many 'if else' statements to a cleaner approach [duplicate]
...h Mimetype like:
public interface Converter {
public void convertToMp3();
public void convertToOgg();
}
public class MpegConverter implements Converter {
public void convertToMp3() {
//Code here
}
public void convertToOgg() {
//Code here
}
}
You would...