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How to modify a global variable within a function in bash?
...alise that if you just run the function without assigning it to a variable all the global variables within it will update. Instead of returning a string array, why not just update the string array in the function then assign it to another variable after the function has finished ?
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String concatenation vs. string substitution in Python
...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>&g...
How to implement a queue with three stacks?
...r Sedgewick have confirmed they are not aware of a 3-stack solution within all the constraints of the original question
DETAILS
There are two implementations behind this link: http://www.eecs.usma.edu/webs/people/okasaki/jfp95/index.html
One of them is O(1) with three stacks BUT it uses lazy exe...
Batch File; List files in directory, only filenames?
...s is probably a very simple question, but I'm having trouble with it. Basically, I am trying to write a Batch File and I need it to list all the files in a certain directory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names and e...
How do I do a not equal in Django queryset filtering?
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Your query appears to have a double negative, you want to exclude all rows where x is not 5, so in other words you want to include all rows where x IS 5. I believe this will do the trick.
results = Model.objects.filter(x=5).exclude(a=true)
To answer your specific question, there is no "...
Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
How to dynamically compose an OR query filter in Django?
...o:
list = [1, 2, 3]
# it gets a bit more complicated if we want to dynamically build
# OR queries with dynamic/unknown db field keys, let's say with a list
# of db fields that can change like the following
# list_with_strings = ['dbfield1', 'dbfield2', 'dbfield3']
# init our q objects variable to ...
In jQuery, how do I get the value of a radio button when they all have the same name?
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@PavanAlapati We cannot really tell you why without seeing your HTML as well; ideally, you would post a new question with your exact HTML snippet and the code you are using. You should only get undefined though, if: The name in the selector does not m...
What does the Q_OBJECT macro do? Why do all Qt objects need this macro?
I just started using Qt and noticed that all the example class definitions have the macro Q_OBJECT as the first line. What is the purpose of this preprocessor macro?
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How to combine two or more querysets in a Django view?
...sets into a list is the simplest approach. If the database will be hit for all querysets anyway (e.g. because the result needs to be sorted), this won't add further cost.
from itertools import chain
result_list = list(chain(page_list, article_list, post_list))
Using itertools.chain is faster than...