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django - query filter on manytomany is empty
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Using AnotherModel.objects.filter(testmodel_set=None) worked for me. If you're using a related name, you should of course use that instead.
– Felipe
Feb 22 '16 at 13:31
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How to get the list of properties of a class?
...of(Foo).GetProperties();
for example:
class Foo {
public int A {get;set;}
public string B {get;set;}
}
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Foo foo = new Foo {A = 1, B = "abc"};
foreach(var prop in foo.GetType().GetProperties()) {
Console.WriteLine("{0}={1}", prop.Name, prop.GetValue(foo, null));
}
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Force R not to use exponential notation (e.g. e+10)?
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In rstudio, if you import a dataset and do train_sample_10k = format(train_sample_10k,scientific=FALSE) and reload, it will change scientific notations.
– mixdev
Nov 23 '14 at 5:21
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Remove CSS from a Div using JQuery
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That would remove the previous settings for background-color and font-weight
– Philippe Leybaert
Jun 5 '09 at 10:09
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Default height for section header in UITableView
I want to set the height of the first header in my UITableView. For the other headers I want them to remain the default height. What value/constant can I put in place of "someDefaultHeight" in the code below?
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What's the difference between '$(this)' and 'this'?
...t keep this in mind.
$(this)[0] === this
Basically every time you get a set of elements back jQuery turns it into a jQuery object. If you know you only have one result, it's going to be in the first element.
$("#myDiv")[0] === document.getElementById("myDiv");
And so on...
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How do I convert a String to an int in Java?
... boolean isNeg = false;
// Check for negative sign; if it's there, set the isNeg flag
if (str.charAt(0) == '-') {
isNeg = true;
i = 1;
}
// Process each character of the string;
while( i < str.length()) {
num *= 10;
num += str.charAt(i++) -...
Deleting array elements in JavaScript - delete vs splice
...yArray[0]
true
> myArray[0]
undefined
Note that it is not in fact set to the value undefined, rather the property is removed from the array, making it appear undefined. The Chrome dev tools make this distinction clear by printing empty when logging the array.
> myArray[0]
undefined
&g...
Thread pooling in C++11
...ctor.clear();
stopped = true; // use this flag in destructor, if not set, call shutdown()
}
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How to reorder data.table columns (without copying)
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Use setcolorder():
library(data.table)
x <- data.table(a = 1:3, b = 3:1, c = runif(3))
x
# a b c
# [1,] 1 3 0.2880365
# [2,] 2 2 0.7785115
# [3,] 3 1 0.3297416
setcolorder(x, c("c", "b", "a"))
x
# c ...