What is the dimensionality of an array and how to judge the dimensionality of an array

Array dimensionality refers to a series of ordered integers in a multidimensional array.

The number of integers in the list of integers that are always the same. In a database, the number of array dimensions is related to the number of attributes in the table, and the more attributes, the larger the array dimension. attributes, common properties and characteristics.

Field properties, resource properties, and those read and modify permissions in the computer. For example: file attributes, user attributes. According to the classification of array dimensions, it can be divided into: one-dimensional array and two-dimensional array.

Multidimensional arrays. <>

It is an element in an array, when represented by an array subscript, it needs to be represented by several numbers to uniquely determine this element, and this array is several dimensions.

For example, a number determines an element: a[7] is one-dimensional.

Two numbers determine an element: b[5][9] is two-dimensional.

The three numbers: C[6][8][1] are three-dimensional.

n numbers are n-dimensional.

You can think of the dimension of an array as "the number of layers of an array of arrays".

For example, an array is a one-dimensional array, and to find the number 9 you just need to find the third number.

is a two-dimensional array. It has two layers of arrays.

To find the number 9, you need to indicate which element 9 is in the outer array, and which element in the inner array. So you need to mark it with two numbers: the first element in the 4th element of the array is 9.

The number of subscripts in an array, e.g. a x y is two-dimensional. a x is one-dimensional.

1. Judge the dimensions first.

Degree – the square bracket at the front of the number.

The first few square brackets are several dimensions. For example.

This is a two-dimensional array.

a = , 2, 3], 4, 5, 6]],7,8,9],[10,11,12]]]

This is a three-dimensional array.

2. Remove the outermost brackets one by one, count the number of braces in it, and multiply it by the corresponding number according to the spring brief.

Like what. a = , 2, 3], 4, 5, 6]],7,8,9],[10,11,12]]]

Remove the outermost brackets.

You can see that there are two large pieces under the pants, so multiply by 2

Take a large piece of slippery blind and study it, and then remove a layer of brackets.

I found that there were still two pieces, so I multiplied it by 2, so now it is 2x2 and then take the previous large block and remove the brackets, and the result is:

It's three, it's been dismantled, so multiply it by three

So the shape of this array is 2x2x3

The index used when accessing each array element individually.

e.g. int a[5]=;

a[0]a[1]

a[2]a[3]

a[4] denotes the

The 0,1,2,3,4 in the parentheses above are the subscripts.

Subscript variables can be used in the program, i.e. the whole of these variables is an array, and the data type of each variable in the array is the same.

When each element in the array has only one subscript ramp, such an array is called a one-dimensional array.

The one-dimensional number scrambling group is a single-structure array composed of numbers arranged in a simple sorting structure. A one-dimensional array is the most basic array in a computer program. Two-dimensional and multi-dimensional arrays can be seen as the result of multiple superpositions of one-dimensional arrays.

Arrays are an important concept in computer programming, and they can be used to easily process large-scale data.

A one-dimensional array is a single-structure array composed of numbers arranged in a simple sorting structure. Arrays are defined in the format "Type Identifier Array Name Constant Expression ". A one-dimensional array is the simplest array, and its logical structure is a linear table.

A two-dimensional array is essentially an array with an array as an array element, which can be seen as the result of multiple superpositions of a one-dimensional array. That is, "array of arrays", and the definition format of the array is "type specifier array name [constant expression] [constant expression]".

A one-dimensional array is easy to understand, and it's just a big box with a lot of elements in it, like a[3], which is a box with three elements.

A two-dimensional array is an array of one-dimensional arrays.

For example, a[3][4] has three chests containing four elements.

Think of an array as the arrangement of a grid on a straight line, and a two-digit array as a grid drawn on a coordinate axis.

A one-dimensional array is a row of boxes, and a two-dimensional array is a number of rows of boxes.

The number of dimensions must be the same for all arrays, which means that in the same array, each element must have the same number of dimensions, i.e. all elements in the array have the same number of dimensions.

This is because each element in the same array should represent the same type of data, and if they have different dimensions in different numbers, it will lead to confusion and inconsistencies in the data.

For example, if the elements in an array are three-dimensional vectors, then the number of dimensions for each element should be 3, representing the component values of the vector in three directions. If the number of dimensions of one of the elements is 2, then it cannot represent a 3D vector, which will lead to inconsistencies in the data.

Therefore, in order to ensure the consistency and correctness of the data, the dimensions of all arrays must be the same.

For programmers, this principle can be followed by specifying the number of dimensions for each element before defining the array, or by using ready-made array libraries that automatically guarantee the same number of dimensions for all elements in the array. At the same time, if the number of dimensions of an element is found to be inconsistent when processing the array, it should be processed in time to avoid data confusion and errors.

The number of dimensions of all arrays must be the same, which means that in a multidimensional array, the number of dimensions (also known as length or size) of each subarray must be the same, which means that the number of elements in each subarray must be the same.

This rule exists to ensure the consistency and reliability of multidimensional arrays. If different subarrays have different sizes, then problems will arise when performing array operations, such as sorting, finding, inserting, deleting, etc.

Therefore, when defining multidimensional arrays, you need to ensure that each subarray is the same size, which can be achieved by specifying the size of each dimension when declaring the array. For example, int[arr = new int[3][4]; A two-dimensional array of 3 rows and 4 columns is defined, where each subarray has 4 elements.

If you need to store data of different sizes, you can use dynamic arrays such as arraylist instead of multidimensional arrays, which can more flexibly handle data of different sizes.

This means that if you want to put multiple arrays together, they must have the same number of dimensions or elements. For example, if you want to combine multiple one-dimensional numbers into one large array, the one-dimensional arrays must all be equal in length. Similarly, if you want to combine multiple 2D numbers into an array, you must have an equal number of rows and columns for each 2D array.

Otherwise, the merged array may not be handled correctly, resulting in incorrect results.

It is important to note that the "number of dimensions" is the number of degrees that need to be specified in the exponential group, for example, a one-dimensional array has only one degree, while a two-dimensional array has two dimensions. If multiple arrays have different dimensions, they cannot be combined into a single array.

All arrays must have the same number of dimensions"This statement means that when performing an array operation, the dimensions of the imaginary groups of multiple numbers involved in the operation must be the same. For example, if you want to add two arrays, the dimensions of the two arrays must be the same in order to be calculated.

The dimensions of an array are the size of the exponential group, how the array elements are stored, and how the array elements are accessed. For example, a one-dimensional array has a dimension of 1, a two-dimensional array has a dimension of 2, a three-dimensional array has a dimension of 3, and so on. If the dimensions of the arrays involved in the operation are inconsistent, the error of dimensionality does not match during the operation.

It is important to note that while the dimensions of the arrays involved in the operation must be the same, they can be different in size, element type, and element value. When performing the calculation, it is necessary to ensure that the subscript of the dimension corresponding to each array is the same in order to carry out the corresponding operation of the elements.