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How does a ArrayList's contains() method evaluate objects?
...object and add it to my ArrayList . If I then create another object with exactly the same constructor input, will the contains() method evaluate the two objects to be the same? Assume the constructor doesn't do anything funny with the input, and the variables stored in both objects are identical....
Fastest way to check if a value exists in a list
What is the fastest way to know if a value exists in a list (a list with millions of values in it) and what its index is?
1...
Awk学习笔记 - 更多技术 - 清泛网 - 专注C/C++及内核技术
Awk学习笔记awk是一种编程语言,用于在linux unix下对文本和数据进行处理。数据可以来自标准输入、一个或多个文件,或其它命令的输出。它支持用户自定义函数和动态正则表达式等先进功能,是linux unix下的一个强大编程工具。
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List OrderBy Alphabetical Order
... looking to quickly sort a Generic List<T> . For the sake of this example, let's say I have a List of a Person type with a property of lastname. How would I sort this List using a lambda expression?
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How to get the client IP address in PHP [duplicate]
...s the most reliable value you can find.
However, they can be behind a proxy server in which case the proxy may have set the $_SERVER['HTTP_X_FORWARDED_FOR'], but this value is easily spoofed. For example, it can be set by someone without a proxy, or the IP can be an internal IP from the LAN behind...
How to assign colors to categorical variables in ggplot2 that have stable mapping?
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For simple situations like the exact example in the OP, I agree that Thierry's answer is the best. However, I think it's useful to point out another approach that becomes easier when you're trying to maintain consistent color schemes across multiple data fr...
Iterating over a numpy array
...erate.
>>> a =numpy.array([[1,2],[3,4],[5,6]])
>>> for (x,y), value in numpy.ndenumerate(a):
... print x,y
...
0 0
0 1
1 0
1 1
2 0
2 1
Regarding the performance. It is a bit slower than a list comprehension.
X = np.zeros((100, 100, 100))
%timeit list([((i,j,k), X[i,j,k]) fo...
Calling filter returns [duplicate]
...
It looks like you're using python 3.x. In python3, filter, map, zip, etc return an object which is iterable, but not a list. In other words,
filter(func,data) #python 2.x
is equivalent to:
list(filter(func,data)) #python 3.x
I think it was changed becau...
Swift Beta performance: sorting arrays
..., 2, 2, 5, 8, 1234]
Both are called in the same program as written.
var x_swift = CInt[](count: n, repeatedValue: 0)
var x_c = CInt[](count: n, repeatedValue: 0)
for var i = 0; i < n; ++i {
x_swift[i] = CInt(random())
x_c[i] = CInt(random())
}
let swift_start:UInt64 = mach_absolute_ti...