In most programming languages, the starting index of a matrix or array is typically 0. This means that the first element is accessed using index 0, followed by index 1 for the second element, and so on. However, some languages, like MATLAB and Fortran, use 1-based indexing, where the first element is accessed with index 1. It's important to be aware of the indexing convention used in the specific programming language you are working with.
To sort all diagonal elements of a matrix (2D array), you can first extract the diagonal elements into a separate list. For a square matrix, this would include elements where the row index equals the column index (i.e., elements at positions (0,0), (1,1), (2,2), etc.). Once you have the list of diagonal elements, sort it using a sorting algorithm or built-in function. Finally, replace the original diagonal elements in the matrix with the sorted values.
(array.length - 1) will find the index of the last element in an array (or -1 if the array is empty).
To dynamically allocate an array, use 'void *realloc(void *array, size_t size)', where array is the pointer you plan on reallocating and size is the new length of the array in bytes.One-dimensional array:{int len = 10;int *array = NULL;array = (int*)realloc(array, len * sizeof(int));}Two-dimensional array:{int xlen = 10;int ylen = 10;int **array2d = NULL;array2d = (int**)realloc(array2d, xlen * sizeof(int*));/* After reallocating array2d, do the same to its contents. */int index;for (index = 0; index < xlen; index++) {array2d[index] = (int*)realloc(array2d[index], ylen * sizeof(int));}array2d[5][5] = 24;/* Clean up. */for (index = 0; index < xlen; index++) {free(array2d[index]);}free(array2d);return 0;}
Array subscripts always have a zero-based index. In languages that allow an n-based index, the index is simply offset by n elements, so the compiler subtracts n from the given index to obtain the zero-based index. Arrays are always zero-based because the first element of an array is found zero elements from the start of the array.
Basically, &array[i]; That is, the memory location for an array object with index i. Or, you can do: (array + i);
By design; it makes the compiler's work easier. 1-based array's addressing-function: Address (array, index) = Address (array) + (index-1)*Elemsize(array) 0-based array's addressing-function: Address (array, index) = Address (array) + index*Elemsize (array)
A matrix IS an array so it is impossible to multiply a matrix without array. The answer to the multiplication of two matrices need not be an array. If the first matrix is a 1xn (row) matrix and the second is an nx1 (column) matrix, then their multiple is a 1x1 matrix which can be considered a scalar.
To sort all diagonal elements of a matrix (2D array), you can first extract the diagonal elements into a separate list. For a square matrix, this would include elements where the row index equals the column index (i.e., elements at positions (0,0), (1,1), (2,2), etc.). Once you have the list of diagonal elements, sort it using a sorting algorithm or built-in function. Finally, replace the original diagonal elements in the matrix with the sorted values.
(array.length - 1) will find the index of the last element in an array (or -1 if the array is empty).
A key is the name of a variable in an array ($array["key"]) and the index is the position it's at ($array = ["key" => 0], the index would be 0). Keys and indices are the same if the array is not associative though ($array = [true], the key holding the value true is named 0 and is at index 0).
To dynamically allocate an array, use 'void *realloc(void *array, size_t size)', where array is the pointer you plan on reallocating and size is the new length of the array in bytes.One-dimensional array:{int len = 10;int *array = NULL;array = (int*)realloc(array, len * sizeof(int));}Two-dimensional array:{int xlen = 10;int ylen = 10;int **array2d = NULL;array2d = (int**)realloc(array2d, xlen * sizeof(int*));/* After reallocating array2d, do the same to its contents. */int index;for (index = 0; index < xlen; index++) {array2d[index] = (int*)realloc(array2d[index], ylen * sizeof(int));}array2d[5][5] = 24;/* Clean up. */for (index = 0; index < xlen; index++) {free(array2d[index]);}free(array2d);return 0;}
matrix
a matrix
Array subscripts always have a zero-based index. In languages that allow an n-based index, the index is simply offset by n elements, so the compiler subtracts n from the given index to obtain the zero-based index. Arrays are always zero-based because the first element of an array is found zero elements from the start of the array.
Basically, &array[i]; That is, the memory location for an array object with index i. Or, you can do: (array + i);
using multidimensional array
A matrix in mathematics is a rectangular array of quantities or expressions set out by rows and columns.