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Dynamically select data frame columns using $ and a character value
...s a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Se...
find() with nil when there are no records
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answered Mar 7 '12 at 15:47
apneadivingapneadiving
109k2525 gold badges208208 silver badges207207 bronze badges
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Is there any way to check if iOS app is in background?
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286
App delegate gets callbacks indicating state transitions. You can track it based on that.
Al...
using awk with column value conditions
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132
If you're looking for a particular string, put quotes around it:
awk '$1 == "findtext" {print $...
Full-screen iframe with a height of 100%
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284
You could use frameset as the previous answer states but if you are insistent on using iFrames...
decimal vs double! - Which one should I use and when? [duplicate]
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answered Jul 22 '09 at 14:42
DavidDavid
22.7k88 gold badges5757 silver badges8080 bronze badges
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Common elements comparison between 2 lists
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282
>>> list1 = [1,2,3,4,5,6]
>>> list2 = [3, 5, 7, 9]
>>> list(set(lis...
What's the difference between `on` and `live` or `bind`?
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329
on() is an attempt to merge most of jQuery's event binding functions into one. This has the ad...
Why is Java's boolean primitive size not defined?
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Short answer: yes, boolean values are manipulated as 32-bit entities, but arrays of booleans use 1 byte per element.
Longer answer: the JVM uses a 32-bit stack cell, used to hold local variables, method arguments, and expression values. Primitives that are smaller than 1 cell a...
Limit labels number on Chart.js line chart
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152
Try adding the options.scales.xAxes.ticks.maxTicksLimit option:
xAxes: [{
type: 'time',
...