Intel® Fortran Compiler 16.0 User and Reference Guide
Array assignment is permitted when the array expression on the right has the same shape as the array variable on the left, or the expression on the right is a scalar.
If the expression is a scalar, and the variable is an array, the scalar value is assigned to every element of the array.
If the expression is an array, the variable must also be an array. The array element values of the expression are assigned (element by element) to corresponding elements of the array variable.
A many-one array section is a vector-valued subscript that has two or more elements with the same value. In intrinsic assignment, the variable cannot be a many-one array section because the result of the assignment is undefined.
In the following example, X and Y are arrays of the same shape:
X = Y
The corresponding elements of Y are assigned to those of X element by element; the first element of Y is assigned to the first element of X, and so forth. The processor can perform the element-by-element assignment in any order.
The following example shows a scalar assigned to an array:
B(C+1:N, C) = 0
This sets the elements B (C+1,C), B (C+2,C),...B (N,C) to zero.
The following example causes the values of the elements of array A to be reversed:
REAL A(20) ... A(1:20) = A(20:1:-1)