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Why is there no xrange function in Python3?
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Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 ...
Quick easy way to migrate SQLite3 to MySQL? [closed]
...ned is: use an ORM class that abstracts specific database differences away for you. e.g. you get these in PHP (RedBean), Python (Django's ORM layer, Storm, SqlAlchemy), Ruby on Rails (ActiveRecord), Cocoa (CoreData)
i.e. you could do this:
Load data from source database using the ORM class.
Stor...
How do I import CSV file into a MySQL table?
...t I'm trying to load into a MySQL table so that I can refactor into a sane format. I created a table called 'CSVImport' that has one field for every column of the CSV file. The CSV contains 99 columns , so this was a hard enough task in itself:
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Rename specific column(s) in pandas
... a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answers
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Numpy - add row to array
...ulation you work against the good work Numpy does in pre-allocating memory for your existing array A. Clearly for small problem like in this answer this isn't a problem, but it can be more troubling for large data.
– dtlussier
Dec 15 '11 at 16:59
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How do I catch a numpy warning like it's an exception (not just for testing)?
I have to make a Lagrange polynomial in Python for a project I'm doing. I'm doing a barycentric style one to avoid using an explicit for-loop as opposed to a Newton's divided difference style one. The problem I have is that I need to catch a division by zero, but Python (or maybe numpy) just makes i...
Doing something before program exit
How can you have a function or something that will be executed before your program quits? I have a script that will be constantly running in the background, and I need it to save some data to a file before it exits. Is there a standard way of doing this?
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Flask raises TemplateNotFound error even though template file exists
... a given template, by setting the EXPLAIN_TEMPLATE_LOADING option to True. For every template loaded, you'll get a report logged to the Flask app.logger, at level INFO.
This is what it looks like when a search is successful; in this example the foo/bar.html template extends the base.html template, ...
How can I implement a tree in Python?
...oe", parent=dan)
print(udo)
Node('/Udo')
print(joe)
Node('/Udo/Dan/Joe')
for pre, fill, node in RenderTree(udo):
print("%s%s" % (pre, node.name))
Udo
├── Marc
│ └── Lian
└── Dan
├── Jet
├── Jan
└── Joe
print(dan.children)
(Node('/Udo/Dan/Jet...
ASP.NET MVC: No parameterless constructor defined for this object
...rameterless constructor.
The call stack was figuring a method responsible for creating a new instance of a model.
System.Web.Mvc.DefaultModelBinder.CreateModel(ControllerContext controllerContext, ModelBindingContext bindingContext, Type modelType)
Here is a sample:
public class MyControll...