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How to reshape data from long to wide format
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The new (in 2014) tidyr package also does this simply, with gather()/spread() being the terms for melt/cast.
Edit: Now, in 2019, tidyr v 1.0 has launched and set spread and gather on a deprecation path, preferring instead pivot_wider and pivot_longer, which you ...
Use Font Awesome Icon in Placeholder
... characters for all non unicode symbols. For me inserting a unicode entity does not work, but pasting in the symbol works: placeholder=" Hello"
– DanielKhan
Nov 11 '13 at 14:38
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How can I format a decimal to always show 2 decimal places?
....quantize(TWOPLACES)
Decimal('3.21')
>>> # Validate that a number does not exceed two places
>>> Decimal('3.21').quantize(TWOPLACES, context=Context(traps=[Inexact]))
Decimal('3.21')
>>> Decimal('3.214').quantize(TWOPLACES, context=Context(traps=[Inexact]))
Traceback (most...
+ operator for array in PHP?
What does + mean for array in PHP?
8 Answers
8
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How to increase font size in a plot in R?
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why cex=1.5 does not work? But have to specify for each part in terms of cex.lab, cex.axis, cex.main? What is cex=1.5 for?
– Tim
Nov 22 '10 at 2:49
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IntelliJ inspection gives “Cannot resolve symbol” but still compiles code
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First of all you should try File | Invalidate Caches and if it doesn't help, delete IDEA system directory. Then re-import the Maven project and see if it helps.
In some weird cases compiled classes may report wrong info and confuse IDEA. Verify that the classes from this jar report corr...
How can I use a local image as the base image with a dockerfile?
...er will try to pull it from the registry.
In other words, if a Dockerfile does FROM ubuntu, but you have a local image called ubuntu different from the official one, your image will override it.
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Javascript Array.sort implementation?
Which algorithm does the JavaScript Array#sort() function use? I understand that it can take all manner of arguments and functions to perform different kinds of sorts, I'm simply interested in which algorithm the vanilla sort uses.
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How to mock void methods with Mockito
... and therefore cannot be mocked. Instead try create()-ing an instance that does what you need. There should be no need to mock RateLimiter.
– dimo414
Jan 19 '16 at 23:31
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What's the difference between isset() and array_key_exists()? [duplicate]
...xists('key2', $a); // true
There is another important difference: isset doesn't complain when $a does not exist, while array_key_exists does.
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