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How can I get a Bootstrap column to span multiple rows?
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167
For Bootstrap 3:
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/boots...
How do I install an old version of Django on virtualenv?
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142
There was never a Django 1.0.7. The 1.0 series only went up to 1.0.4. You can see all the rele...
Which is the first integer that an IEEE 754 float is incapable of representing exactly?
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215
2mantissa bits + 1 + 1
The +1 in the exponent (mantissa bits + 1) is because, if the mantissa ...
How to increment a pointer address and pointer's value?
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171
First, the ++ operator takes precedence over the * operator, and the () operators take precede...
Why is MySQL's default collation latin1_swedish_ci?
What is the reasoning behind setting latin1_swedish_ci as the compiled default when other options seem much more reasonable, like latin1_general_ci or utf8_general_ci ?
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...
Transparent ARGB hex value
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edited Feb 18 '16 at 5:17
Robert
1,5081818 silver badges3333 bronze badges
answered Apr 2...
Generate array of all letters and digits
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145
[*('a'..'z'), *('0'..'9')] # doesn't work in Ruby 1.8
or
('a'..'z').to_a + ('0'..'9').to_a ...
sed: print only matching group
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140
Match the whole line, so add a .* at the beginning of your regex. This causes the entire line ...
Get item in the list in Scala?
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311
Use parentheses:
data(2)
But you don't really want to do that with lists very often, since l...