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Difference between map and collect in Ruby?
...well: In C++'s Standard Template Library, it is called transform, in C# (3.0)'s LINQ library, it is provided as an extension method called Select. Map is also a frequently used operation in high level languages such as Perl, Python and Ruby; the operation is called map in all three of these language...
Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?
...nditions = new List<string>();
if (condition1) conditions.Add("Col1=0");
//...
if (conditions.Any())
Query += " WHERE " + string.Join(" AND ", conditions.ToArray());
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Increase number of axis ticks
...continuous. For example:
library(ggplot2)
dat <- data.frame(x = rnorm(100), y = rnorm(100))
ggplot(dat, aes(x,y)) +
geom_point()
Gives you this:
And overriding the scales can give you something like this:
ggplot(dat, aes(x,y)) +
geom_point() +
scale_x_continuous(breaks = round(seq(m...
Using custom std::set comparator
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answered Apr 12 '10 at 9:10
YacobyYacoby
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MySQL remove all whitespaces from the entire column
...
203
To replace all spaces :
UPDATE `table` SET `col_name` = REPLACE(`col_name`, ' ', '')
To remo...
What's the difference between HEAD^ and HEAD~ in Git?
...it rev-parse documentation defines it as
<rev>^, e.g. HEAD^, v1.5.1^0
A suffix ^ to a revision parameter means the first parent of that commit object. ^<n> means the nth parent ([e.g.] <rev>^ is equivalent to <rev>^1). As a special rule, <rev>^0 means the commit itself...
Using helpers in model: how do I include helper dependencies?
...om a text area. Following the advice from http://blog.caboo.se/articles/2008/8/25/sanitize-your-users-html-input , I'm cleaning up the input in the model before saving to database, using the before_validate callback.
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Pythonic way of checking if a condition holds for any element of a list
...
any():
if any(t < 0 for t in x):
# do something
Also, if you're going to use "True in ...", make it a generator expression so it doesn't take O(n) memory:
if True in (t < 0 for t in x):
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List of tuples to dictionary
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Boris
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answered Jun 29 '11 at 14:36
Sven MarnachSven Ma...
input type=file show only button
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answered Feb 11 '13 at 6:07
shibashiba
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