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A Regex that will never be matched by anything
This might sound like a stupid question, but I had a long talk with some of my fellow developers and it sounded like a fun thing to think of.
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How to plot two histograms together in R?
I am using R and I have two data frames: carrots and cucumbers. Each data frame has a single numeric column which lists the length of all measured carrots (total: 100k carrots) and cucumbers (total: 50k cucumbers).
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What's the best way to iterate over two or more containers simultaneously
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Rather late to the party. But: I would iterate over indices. But not with the classical for loop but instead with a range-based for loop over the indices:
for(unsigned i : indices(containerA)) {
containerA[i] = containerB[i];
}
indices is a sim...
Choosing between qplot() and ggplot() in ggplot2 [closed]
...plot2 package for plotting in R, and one of the first things I ask myself before each plot is "well, will I use qplot or ggplot ?"
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Postgres - FATAL: database files are incompatible with server
After restarting my MacBook Pro I am unable to start the database server:
6 Answers
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How to generate the “create table” sql statement for an existing table in postgreSQL
I have created a table in postgreSQL. I want to look at the SQL statement used to create the table but cannot figure it out.
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What is PostgreSQL explain telling me exactly?
...etty straightforward. PostgreSQL's is a little more complicated. I haven't been able to find a good resource that explains it either.
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Find value in an array
In Ruby, how can I find a value in an array?
10 Answers
10
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Why does Pycharm's inspector complain about “d = {}”?
...:
dic = {}
dic['aaa'] = 5
as you could have written
dic = {'aaa': 5}
BTW: The fact that the error goes away if you use the function doesn't necessarily mean that pycharm believes dict() is a literal. It could just mean that it doesn't complain for:
dic = dict()
dic['aaa'] = 5
HTH!
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Covariance and contravariance real world example
I'm having a little trouble understanding how I would use covariance and contravariance in the real world.
9 Answers
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