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How to use Active Support core extensions
I have Active Support 3.0.3 installed and Rails 3.0.3 with Ruby 1.8.7.
5 Answers
5
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Split string with delimiters in C
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165
You can use the strtok() function to split a string (and specify the delimiter to use). Note t...
How to format strings in Java
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140
In addition to String.format, also take a look java.text.MessageFormat. The format less terse...
How can I shrink the drawable on a button?
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16 Answers
16
Active
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How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
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edited Sep 8 '19 at 2:45
answered Jul 25 '10 at 15:04
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Are there any O(1/n) algorithms?
Are there any O(1/n) algorithms?
32 Answers
32
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Text border using css (border around text)
...:
text-shadow: 2px 0 0 #fff, -2px 0 0 #fff, 0 2px 0 #fff, 0 -2px 0 #fff, 1px 1px #fff, -1px -1px 0 #fff, 1px -1px 0 #fff, -1px 1px 0 #fff;
body {
font-family: sans-serif;
background: #222;
color: darkred;
}
h1 {
text-shadow: 2px 0 0 #fff, -2px 0 0 #fff, 0 2px 0 #fff, 0 -2px...
Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
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Is it safe to check floating point values for equality to 0?
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115
It is safe to expect that the comparison will return true if and only if the double variable h...
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 ...