For multidimensional arrays, the column-major form of allocation can be used only if all array indices must be specified together.
Select one:
True
False
The correct answer and explanation is:
The correct answer is True.
In column-major order, elements of a multidimensional array are stored in memory column by column. This means that all elements in the first column are stored first, followed by the elements in the second column, and so on. To properly reference an element in a multidimensional array using column-major allocation, all indices of the array must be specified together, meaning both the row and column indices (or the equivalent in higher dimensions) must be given at once to determine the exact memory location of the element.
This is because the layout of data in memory is continuous along the columns. In programming languages like Fortran (which uses column-major order by default), accessing the array elements involves referring to the specific row and column in order to accurately determine the element’s position in memory.
When all indices are specified together, it allows for efficient memory access because the array elements in the same column are stored contiguously in memory. This makes it easier for the system to retrieve data without needing additional calculations or indirect references to figure out where the element resides in memory. However, if the indices are not specified together (e.g., one index is known and the other is determined dynamically), accessing the data can be inefficient or even incorrect in column-major systems.
In contrast, row-major order (used by languages like C and Python) stores elements row by row. This difference is important for optimizing memory access patterns, and programming languages must consider it when designing how arrays are allocated in memory. In column-major allocation, specifying all indices is crucial to make full use of the memory layout, ensuring correct and efficient access to the multidimensional array.