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How exactly does the python any() function work?
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If you use any(lst) you see that lst is the iterable, which is a list of some items. If it con...
Regular expression \p{L} and \p{N}
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\p{L} matches a single code point in the category "letter".
\p{N} matches any kind of num...
How to write a Ruby switch statement (case…when) with regex and backreferences?
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The references to the latest regex matching groups are always stored in pseudo variables $1 to...
How do you compare two version Strings in Java?
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edited Jan 12 '15 at 15:35
Balder
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How accurately should I store latitude and longitude?
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Accuracy versus decimal places at the equator
decimal degrees distance
places
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Why are floating point numbers inaccurate?
...gnificand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is impossible to represent some decimal numbers this way is that both the exponent and the mantissa must be integers. In ...
Get String in YYYYMMDD format from JS date object?
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...e .drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$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 ...
Java: parse int value from a char
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edited Apr 30 '18 at 4:24
Neuron
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answ...