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How to split data into training/testing sets using sample function
...row(mtcars))
## set the seed to make your partition reproducible
set.seed(123)
train_ind <- sample(seq_len(nrow(mtcars)), size = smp_size)
train <- mtcars[train_ind, ]
test <- mtcars[-train_ind, ]
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How to remove a field completely from a MongoDB document?
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14 Answers
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Does python have an equivalent to Java Class.forName()?
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169
Reflection in python is a lot easier and far more flexible than it is in Java.
I recommend re...
Get most recent file in a directory on Linux
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21 Answers
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What is the usefulness of PUT and DELETE HTTP request methods?
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For the full specification visit:
http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
Since current browsers unfortunately do not support any other verbs than POST and GET in HTML forms, you usually cannot utilize HTTP to it's full extent with them (you can still hijack their submission ...
Why is using the rails default_scope often recommend against?
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193
Problem 1
Lets consider the basic example:
class Post < ActiveRecord::Base
default_sco...
GraphViz - How to connect subgraphs?
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197
The DOT user manual gives the following example of a graph with clusters with edges between cl...
What does $(function() {} ); do?
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314
$(function() { ... });
is just jQuery short-hand for
$(document).ready(function() { ... });...
sed beginner: changing all occurrences in a folder
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149
There is no way to do it using only sed. You'll need to use at least the find utility together...
Get current time in seconds since the Epoch on Linux, Bash
I need something simple like date , but in seconds since 1970 instead of the current date, hours, minutes, and seconds.
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