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Simple calculations for working with lat/lon and km distance?
...ula using the WGS84 reference ellipsoid (the model used for GPS). But the error is probably negligible for your purposes.
Source: http://en.wikipedia.org/wiki/Latitude
Caution: Be aware that latlong coordinates are expressed in degrees, while the cos function in most (all?) languages typically ac...
Django dynamic model fields
...ister(Patient)
Attribute.objects.create(name='age', datatype=Attribute.TYPE_INT)
Attribute.objects.create(name='height', datatype=Attribute.TYPE_FLOAT)
Attribute.objects.create(name='weight', datatype=Attribute.TYPE_FLOAT)
Attribute.objects.create(name='city', datatype=Attribute.TYPE_TEXT)
Attribute...
Filter by property
... them:
With a Manager:
class CompanyManager(models.Manager):
def with_chairs_needed(self):
return self.annotate(chairs_needed=F('num_employees') - F('num_chairs'))
class Company(models.Model):
# ...
objects = CompanyManager()
Company.objects.with_chairs_needed().filter(chairs...
Best practice to make a multi language application in C#/WinForms? [closed]
...nually setting the labels in the form load. This file can also be used for error messages etc.
A question of taste...
One last point, I write programs in English and French, I use "en" and "fr" and not "en-US" and "fr-FR". Do not complicate things, the different dilelects of English (American, Eng...
Can I create links with 'target=“_blank”' in Markdown?
...d, you'll just have to use HTML.
<a href="http://example.com/" target="_blank">Hello, world!</a>
Most Markdown engines I've seen allow plain old HTML, just for situations like this where a generic text markup system just won't cut it. (The StackOverflow engine, for example.) They then...
python: how to identify if a variable is an array or a scalar
...o uses numpy often, I'd recommend a very pythonic test of:
if hasattr(N, "__len__")
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Is there an expression for an infinite generator?
...te itertools.count: count = lambda start=0, step=1: (start + i*step for i, _ in enumerate(iter(int, 1)))
– Coffee_Table
Aug 13 '18 at 23:43
2
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sqlalchemy unique across multiple columns
... declares those in the table definition, or if using declarative as in the __table_args__:
# version1: table definition
mytable = Table('mytable', meta,
# ...
Column('customer_id', Integer, ForeignKey('customers.customer_id')),
Column('location_code', Unicode(10)),
UniqueConstraint...
Bundler: Command not found
...wing some tutorials. If I run bundle check or bundle install I get the error '-bash: bundle: command not found'. From gem list --local I see 'bundler (1.0.2, 1.0.0)' is installed.
...
Regex Named Groups in Java
...> TEST
matcher.name(1) ==> login
Replace
matcher.replaceAll("aaaaa_$1_sssss_$2____") ==> aaaaa_TEST_sssss_123____
matcher.replaceAll("aaaaa_${login}_sssss_${id}____") ==> aaaaa_TEST_sssss_123____
(extract from the implementation)
public final class Pattern
implements java.io...