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Django set default form values
...ch is explained here
You have two options either populate the value when calling form constructor:
form = JournalForm(initial={'tank': 123})
or set the value in the form definition:
tank = forms.IntegerField(widget=forms.HiddenInput(), initial=123)
...
Variable interpolation in the shell
I have a variable called filepath=/tmp/name .
3 Answers
3
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Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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Finding the index of elements based on a condition using python list comprehension
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In Python, you wouldn't use indexes for this at all, but just deal with the values—[value for value in a if value > 2]. Usually dealing with indexes means you're not doing something the best way.
If you do need an API similar to Matlab's, you would use numpy, a packag...
MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
Adding a cross-reference to a subheading or anchor in another page
... because it works across files, when section headings are changed, and for all builders that support cross-references.
RST, in General
The tools that convert RST files to HTML do not necessarily have a notion of collection. This is the case for instance if you rely on github to convert RST files ...
Where does Scala look for implicits?
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Implicits in Scala refers to either a value that can be passed "automatically", so to speak, or a conversion from one type to another that is made automatically.
Implicit Conversion
Speaking very briefly about the latter type, if one calls a method m on an object o of a class C, and that class d...
How to get the currently logged in user's user id in Django?
...rs = [{user.id: user.get_name()} for user in logged_in_users]
# Query all logged in staff users based on id list
all_staff_users = CustomUser.objects.filter(is_resident=False, is_active=True, is_superuser=False)
logged_out_users = list()
# for some reason exclude() would not work co...
Is there any way to kill a Thread?
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It is generally a bad pattern to kill a thread abruptly, in Python and in any language. Think of the following cases:
the thread is holding a critical resource that must be closed properly
the thread has created several other threads ...
What does enumerate() mean?
...ieving that; one using itertools.count() to do the counting, the other manually counting in a generator function:
from itertools import count
def enumerate(it, start=0):
# return an iterator that adds a counter to each element of it
return zip(count(start), it)
and
def enumerate(it, sta...