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In C# and Java [5] jagged arrays can be created with the following code: [6] int [][] ... In C and C++, a jagged array can be created (on the stack) using the ...
In C and C++ arrays do not support the size function, so programmers often have to declare separate variable to hold the size, and pass it to procedures as a separate parameter. Elements of a newly created array may have undefined values (as in C), or may be defined to have a specific "default" value such as 0 or a null pointer (as in Java).
Elements can be removed from the end of a dynamic array in constant time, as no resizing is required. The number of elements used by the dynamic array contents is its logical size or size, while the size of the underlying array is called the dynamic array's capacity or physical size, which is the maximum possible size without relocating data. [2]
Array programming is very well suited to implicit parallelization; a topic of much research nowadays.Further, Intel and compatible CPUs developed and produced after 1997 contained various instruction set extensions, starting from MMX and continuing through SSSE3 and 3DNow!, which include rudimentary SIMD array capabilities.
Another common use of vectorized indices is a filtering operation. Consider a clipping operation of a sine wave where amplitudes larger than 0.5 are to be set to 0.5. Using S-Lang, this can be done by y = sin(x); y[where(abs(y)>0.5)] = 0.5;
For a vector with linear addressing, the element with index i is located at the address B + c · i, where B is a fixed base address and c a fixed constant, sometimes called the address increment or stride. If the valid element indices begin at 0, the constant B is simply the address of the first element of the array.
C struct data types may end with a flexible array member [1] with no specified size: struct vectord { short len ; // there must be at least one other data member double arr []; // the flexible array member must be last // The compiler may reserve extra padding space here, like it can between struct members };
DECLARE X(5,5); DECLARE Y(5) DEFINED(X(1SUB,1SUB)); A reference to Y(2) is a reference to X(2,2), and so on. A slice, called a cross-section, of an array can be referred to by using asterisk as the subscript for one or more dimensions. The following code sets all the elements in the first column of X to zero. One or more subscripts can be ...