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How to do a less than or equal to filter in Django queryset?

I am attempting to filter users by a custom field in each users profile called profile. This field is called level and is an integer between 0-3. ...
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How to remove an item from an array in AngularJS scope?

... Your issue is not really with Angular, but with Array methods. The proper way to remove a particularly item from an array is with Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current inde...
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Union of dict objects in Python [duplicate]

...yptic, and it immediately makes most readers balk and the remainder assume all the keys in x would have to be legal parameter names. IMHO, the fact it works is a bug in the name-checking mechanisms in the implementation. What happens when you rely on bugs? They either get fixed, or become politic...
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Pragma in define macro

...ay of doing that. Then again, there are no portable ways to use #pragma at all. Because of this, many C/C++ compilers define their own methods for doing pragma-like things, and they often can be embedded in macros, but you need a different macro definition on every compiler. If you are willing to go...
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Why is there no xrange function in Python3?

...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 s per loop Now, python.org 3.3.0 64-bit: In [83]: %timeit collec...
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Where can I learn how to write C code to speed up slow R functions? [closed]

...ds C++ and Rcpp to be much more like writing R than writing C++. YMMV and all that. share | improve this answer | follow | ...
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How do I write a short literal in C++?

...rt enough to compile this as if it's a short literal (i.e. it wouldn't actually allocate an int and then cast it every time). The following illustrates how much you should worry about this: a = 2L; b = 2.0; c = (short)2; d = '\2'; Compile -> disassemble -> movl $2, _a movl $2, _b m...
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Progress indicator during pandas operations

...se you're interested in how this works (and how to modify it for your own callbacks), see the examples on github, the full documentation on pypi, or import the module and run help(tqdm). Other supported functions include map, applymap, aggregate, and transform. EDIT To directly answer the original ...
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How to plot two columns of a pandas data frame using points?

... You can specify the style of the plotted line when calling df.plot: df.plot(x='col_name_1', y='col_name_2', style='o') The style argument can also be a dict or list, e.g.: import numpy as np import pandas as pd d = {'one' : np.random.rand(10), 'two' : np.random.rand(...
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Detecting Unsaved Changes

...reunload methods as required. From the comments, the following references all input fields, without duplicating code: $(':input').change(function () { Using $(":input") refers to all input, textarea, select, and button elements. ...