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Django - how to create a file and save it to a model's FileField?
...hought it was worth while putting this here as it took me a little bit of fiddling to get all the desirable behaviour (overwrite existing file, storing to the right spot, not creating duplicate files etc).
Django 1.4.1
Python 2.7.3
#Model
class MonthEnd(models.Model):
report = models.FileFiel...
What does -save-dev mean in npm install grunt --save-dev
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I tried to understand and I didn't. Then I tried to understand the visualization and I didn't. What does each bullet-point item mean? A folder? What the strikethrough item mean? A non-existing directory? If that is true, how can you list exhaustively non...
How is “int* ptr = int()” value initialization not illegal?
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int() is a constant expression with a value of 0, so it's a valid way of producing a null pointer constant. Ultimately, it's just a slightly different way of saying int *ptr = NULL;
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What is the difference between C, C99, ANSI C and GNU C?
...y named ISO/IEC 9899:1990/Amd.1:1995. The main change was introduction of wide character support.
In 1999, the C standard went through a major revision (ISO 9899:1999). This version of the standard is called C99. From 1999-2011, this was "the C language".
In 2011, the C standard was changed again ...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...= 0 * INF = NaN. INFrsqrt(INF) = INF * 0 = NaN. For this reason, CUDA on NVIDIA GPUs computes approximate single-precision square roots as recip(rsqrt(x)), with the hardware providing both a fast approximation to the reciprocal and the reciprocal square root. Obviously, explicit checks handling the ...
What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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Typescript: difference between String and string
...ifferences, which will help with the explanation.
var s1 = new String("Avoid newing things where possible");
var s2 = "A string, in TypeScript of type 'string'";
var s3: string;
String is the JavaScript String type, which you could use to create new strings. Nobody does this as in JavaScript the ...
How to create a new database using SQLAlchemy?
...cute() however, because postgres does not allow you to create databases inside transactions, and sqlalchemy always tries to run queries in a transaction. To get around this, get the underlying connection from the engine:
>>> conn = engine.connect()
But the connection will still be insid...
“new” keyword in Scala
...o instantiate Java objects only?
With Scala 3 (which should be released mid 2020, eight years later), based on Dotty: never.
Scala 3 will drop "new", as in this thread
Creator applications allow to use simple function call syntax to create instances
of a class, even if there is no apply met...
What is the equivalent of “none” in django templates?
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Any idea how to use this with other filters such as date? For example, is it possible to display "N/A" if a date is none but otherwise format it? Like: {{ post.pub_date|default_if_none:"N/A"|date:"Y-m-d" }}?
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