ubound function usage

The syntax of the ubound function is "ubound(array, dimension)", array is the array to obtain the upper limit of the boundary, and dimension is the array dimension to obtain the upper limit of the boundary. The ubound function returns the upper bound of the array, not the size of the array. Therefore, when using the ubound function, you need to pay attention to distinguishing it from the size of the array.

ubound is a function commonly used in programming languages, such as in Fortran. This function is used to get the upper limit of the array. However, it should be noted that different programming languages ​​may have different usage and syntax. Here we take Fortran as an example to explain the usage of ubound function.

In Fortran, the ubound function is used to obtain the upper bound of an array. It is often used in loop control to avoid out-of-bounds errors when accessing array elements. The syntax of the ubound function is as follows:

ubound(array, dimension)

where: array is the array to obtain the upper limit of the boundary. dimension is the dimension of the array to obtain the upper limit of the bounds.

The following is a simple example that demonstrates how to use the ubound function:

program ubound_example  
    implicit none  
    integer, dimension(3,3) :: array  
    integer :: i, j  
  
    ! 初始化数组  
    array = 0  
    array(1,:) = [1,2,3]  
    array(2,:) = [4,5,6]  
    array(3,:) = [7,8,9]  
  
    ! 打印数组元素  
    do i = 1, ubound(array, 1)  
        do j = 1, ubound(array, 2)  
            write(*, '(i3)') array(i,j)  
        end do  
        write(*, *)  
    end do  
end program ubound_example

In the above example, we declare a 3x3 integer array array and use the ubound function to obtain the array the upper limit of the boundary. In the loop, we use the ubound function to control the dimensions of the array so that we can access the array elements correctly. The output will be a 3x3 matrix where each element is the corresponding element of the array array.

It should be noted that the ubound function returns the upper bound of the array, not the size of the array (that is, the total number of elements). Therefore, when using the ubound function, you need to pay attention to distinguishing it from the size of the array. For example, if the size of a one-dimensional array is 10, then its upper bound is 10. If you try to access an element with an index greater than 10, an out-of-bounds error will result. Use the ubound function to ensure that you don't go out of bounds when accessing array elements.

The above is the detailed content of ubound function usage. For more information, please follow other related articles on the PHP Chinese website!