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ggplot2 keep unused levels barplot
I want to plot unused levels (that is, levels where the count is 0) in my bar-plot, however, unused levels are dropped and I cannot figure out how to keep them
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Python add item to the tuple
I have some object.ID-s which I try to store in the user session as tuple. When I add first one it works but tuple looks like (u'2',) but when I try to add new one using mytuple = mytuple + new.id got error can only concatenate tuple (not "unicode") to tuple .
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How to get row from R data.frame
...- structure(list(A = c(5, 3.5, 3.25, 4.25, 1.5 ),
B = c(4.25, 4, 4, 4.5, 4.5 ),
C = c(4.5, 2.5, 4, 2.25, 3 )
),
.Names = c("A", "B", "C"),
class = "data.frame",
row.names = c...
dynamic_cast and static_cast in C++
...types are not related, you will get a compiler error. For example:
class B {};
class D : public B {};
class X {};
int main()
{
D* d = new D;
B* b = static_cast<B*>(d); // this works
X* x = static_cast<X*>(d); // ERROR - Won't compile
return 0;
}
dynamic_cast< Type* >(p...
Sorting object property by values
If I have a JavaScript object such as:
38 Answers
38
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Find the max of two or more columns with pandas
I have a dataframe with columns A , B . I need to create a column C such that for every record / row:
2 Answers
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JavaScript pattern for multiple constructors
...loading, including for methods or constructors.
If you want a function to behave differently depending on the number and types of parameters you pass to it, you'll have to sniff them manually. JavaScript will happily call a function with more or fewer than the declared number of arguments.
functio...
Assign multiple columns using := in data.table, by group
What is the best way to assign to multiple columns using data.table ? For example:
2 Answers
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Android应用开发性能优化完全分析 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...Layout和requestLayout按钮的功能更加强大，它可以帮助我们debug自定义View执行invalidate()和requestLayout()过程，我们只需要在代码的相关地方打上断点就行了，接下来通过它观察绘制即可。
可以发现，有了HierarchyViewer调试工具，我们的...
Javascript - sort array based on another array
Is it possible to sort and rearrange an array that looks like this:
21 Answers
21
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