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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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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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Why does the arrow (->) operator in C exist?
...as two questions: 1) why -> even exists, and 2) why . does not automatically dereference the pointer. Answers to both questions have historical roots.
Why does -> even exist?
In one of the very first versions of C language (which I will refer as CRM for "C Reference Manual", which came with ...
MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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java: Class.isInstance vs Class.isAssignableFrom
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Both answers are in the ballpark but neither is a complete answer.
MyClass.class.isInstance(obj) is for checking an instance. It returns true when the parameter obj is non-null and can be cast to MyClass without raising a ClassCastException. In ot...
Why do most C developers use define instead of const? [duplicate]
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@C. Ross: Consistency. All manifest constants are usually defined with #defines. const is only used to indicate a read-only (access path to a) variable. I know, const in C is just plain broken :-)
– Bart van Ingen Schenau
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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
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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...
What is the difference between `throw new Error` and `throw someObject`?
...t what we can extract from it in an event of an error? The Error object in all browsers support the following two properties:
name: The name of the error, or more specifically, the name of the constructor function the error belongs to.
message: A description of the error, with this description var...
What is boxing and unboxing and what are the trade offs?
... that are minimal wrappers around primitive types*. Boxed values are typically stored as pointers to objects on the heap.
Thus, boxed values use more memory and take at minimum two memory lookups to access: once to get the pointer, and another to follow that pointer to the primitive. Obviously th...
How can two strings be concatenated?
...','b'),'blah', c(1,2,3)) results in "a blah 1" "b blah 2" "a blah 3". Basically, it creates a vector of strings the same length as the longest vector that's passed in, and loops the other vectors/strings to the same length. Plenty of room for accidental behaviour there.
– naugh...