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How do you validate a URL with a regular expression in Python?
...he result of parsing gives you a netloc or path you don't like, you could call that "invalid".
– S.Lott
Jun 29 '09 at 20:44
2
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Linq to Sql: Multiple left outer joins
...
This may be cleaner (you dont need all the into statements):
var query =
from order in dc.Orders
from vendor
in dc.Vendors
.Where(v => v.Id == order.VendorId)
.DefaultIfEmpty()
from status
in dc.Status
.Where(...
What does 'super' do in Python?
...
What's the difference?
SomeBaseClass.__init__(self)
means to call SomeBaseClass's __init__. while
super(Child, self).__init__()
means to call a bound __init__ from the parent class that follows Child in the instance's Method Resolution Order (MRO).
If the instance is a subclass of ...
Algorithm to compare two images
...t finds 4% of positives in our test data. However, one algorithm may find all the matches, but also have a large 20% false positive rate, so there are several ways to rate your algorithms.
The test data should attempt to be designed to cover as many types of dynamics as possible that you would exp...
Difference between a SOAP message and a WSDL?
...ok like.
The types would look like this;
<wsdl:types>
<!-- all type declarations are in a chunk of xsd -->
<xsd:schema targetNamespace="http://namespaces.my-example-book-info.com"
xmlns:xsd="http://www.w3.org/1999/XMLSchema">
<xsd:element name="GetBookPrice">...
Python debugging tips [closed]
... same effect in the running code
ipdb is a version of pdb for IPython. It allows the use of pdb with all the IPython features including tab completion.
It is also possible to set pdb to automatically run on an uncaught exception.
Pydb was written to be an enhanced version of Pdb. Benefits?
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Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
What are the rules about using an underscore in a C++ identifier?
...FC background, you'll probably use m_foo . I've also seen myFoo occasionally.
5 Answers
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Update MongoDB field using value of another field
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The best way to do this is in version 4.2+ which allows using of aggregation pipeline in the update document and the updateOne, updateMany or update collection method. Note that the latter has been deprecated in most if not all languages drivers.
MongoDB 4.2+
Version 4.2 ...
Getting MAC Address
... says that it will return a random long if it fails to detect the mac: "If all attempts to obtain the hardware address fail, we choose a random 48-bit number with its eighth bit set to 1 as recommended in RFC 4122." So check that eighth bit!
– deinonychusaur
Fe...