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Why are Objective-C delegates usually given the property assign instead of retain?
I'm surfing through the wonderful blog maintained by Scott Stevenson, and I'm trying to understand a fundamental Objective-C concept of assigning delegates the 'assign' property vs 'retain'. Note, the both are the same in a garbage collected environment. I'm mostly concerned with a non-GC based envi...
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...
Postgres - FATAL: database files are incompatible with server
After restarting my MacBook Pro I am unable to start the database server:
6 Answers
6...
Find value in an array
In Ruby, how can I find a value in an array?
10 Answers
10
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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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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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Remove border from IFrame
How would I remove the border from an iframe embedded in my web app? An example of the iframe is:
25 Answers
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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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split string only on first instance - java
I want to split a string by '=' charecter. But I want it to split on first instance only. How can I do that ? Here is a JavaScript example for '_' char but it doesn't work for me
split string only on first instance of specified character
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