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Best practices for overriding isEqual: and hash
...ing to have all sorts of problems when trying to use them as keys in a hashtable (or any dictionary-type collections).
On the other hand, if 2 instances are not equal, they may or may not have the same hash - it is best if they don't. This is the difference between an O(1) search on a hash table...
What are good examples of genetic algorithms/genetic programming solutions? [closed]
...Joel: of course it did, but that's not why I think it would have been profitable. It would have made money because of the heavy bias towards buying instead of selling. A system that just bought S&P500 futures at random times between 1995 and 1999 (without any kind of GA nonsense going on) would ...
How to print a number with commas as thousands separators in JavaScript
...may or may not be an issue, depending on the context. If used for a giant table of 1000 results then it will be more important but if only used for a single value, the difference is negligible. But the advantage is that it's locale-aware, so someone in Europe would see 34.523.453,345 or 34 523 453...
Remove the cell highlight color of UITableView
I want to remove the default blue color of uitableview cell selection. I don't want any selection color there. I have not created a custom cell class. I'm customizing the cell by adding labels and buttons over it.
I tried doing:
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How to auto-scroll to end of div when data is added? [duplicate]
I have a table inside of a div with the following style:
2 Answers
2
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Concatenate multiple result rows of one column into one, group by another column [duplicate]
I'm having a table like this
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Check if a given key already exists in a dictionary
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@Mohan Gulati: You understand that a dictionary is a hashtable of keys mapped to values, right? A hashing algorithm converts the key to an integer and the integer is used to find a location in the hash table that matches. en.wikipedia.org/wiki/Hash_table
– hug...
How to set the width of a cell in a UITableView in grouped style
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A better and cleaner way to achieve this is subclassing UITableViewCell and overriding its -setFrame: method like this:
- (void)setFrame:(CGRect)frame {
frame.origin.x += inset;
frame.size.width -= 2 * inset;
[super setFrame:frame];
}
Why is it better? Because the oth...
How do you manually execute SQL commands in Ruby On Rails using NuoDB
...n.execute("foo")
with "foo" being the sql statement( i.e. "SELECT * FROM table").
This command will return a set of values as a hash and put them into the results variable.
So on my rails application_controller.rb I added this:
def execute_statement(sql)
results = ActiveRecord::Base.connectio...
What is an SSTable?
In BigTable/GFS and Cassandra terminology, what is the definition of a SSTable?
4 Answers
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