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Is it faster to count down than it is to count up?
... technique.
Also, a good optimizing compiler these days should be able to convert your count up loop source code into count down to zero machine code (depending on how you use the loop index variable) so there really isn't any reason to write your loops in strange ways just to squeeze a cycle or tw...
Select by partial string from a pandas DataFrame
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Is it possible to convert .str.contains to use .query() api?
– zyxue
Mar 1 '17 at 17:25
3
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what is the difference between OLE DB and ODBC data sources?
...g to happen for a number of reasons, such as:
The world was not going to convert to Microsoft technologies and
away from ODBC;
DAO/ODBC was faster than ADO/OLE DB and was also thoroughly integrated into MS Access, so wasn’t going to die a natural death;
New technologies that were being developed...
Output array to CSV in Ruby
...{ |csv, row| csv << CSV.generate_line(row) }.join(""))}
NOTE:
To convert an active record database to csv would be something like this I think
CSV.open(fn, 'w') do |csv|
csv << Model.column_names
Model.where(query).each do |m|
csv << m.attributes.values
end
end
H...
Why do we need tuples in Python (or any immutable data type)?
...
if I must convert a tuple to a set or list to be able to sort them, what's the point of using a tuple in the first place?
In this particular case, there probably isn't a point. This is a non-issue, because this isn't one of the cases...
performSelector may cause a leak because its selector is unknown
...s for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:selector];
void (*func)(id, SEL) = (void *)imp;
func(_contr...
Why does 'continue' behave like 'break' in a Foreach-Object?
...re is a gotcha to be kept in mind when refactoring. Sometimes one wants to convert a foreach statement block into a pipeline with a ForEach-Object cmdlet (it even has the alias foreach that helps to make this conversion easy and make mistakes easy, too). All continues should be replaced with return....
Javascript calculate the day of the year (1 - 366)
...));
Which outputs for the leap year 2016 (verified using http://www.epochconverter.com/days/2016):
1/1/2016 is 1 days into the year
2/1/2016 is 32 days into the year
3/1/2016 is 61 days into the year
6/1/2016 is 153 days into the year
12/31/2016 is 366 days into the year
...
What Are the Differences Between PSR-0 and PSR-4?
...k for Acme\Foo\Bar in src/Bar.php(where Bar class is).
2. PSR-4 does not convert underscores to directory separators
3. You would prefer using PSR-4 with namespaces
4. PSR-0 will not work even if the class name is different from file name, like considering above example:
Acme\Foo\Bar --->...
What do the terms “CPU bound” and “I/O bound” mean?
What do the terms "CPU bound" and "I/O bound" mean?
11 Answers
11
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