Threaded

Threaded[list] is an object whose elements will automatically be threaded into the lowest level of an array when used in a listable operation such as Plus.

• a + Threaded[b] adds elements of an array b to elements of an array a at the lowest possible level.
• a + Threaded[b, alev] adds elements at level alev of a.
• a + Threaded[b, blev -> alev] adds elements at level alev in a to level blev in b.
• f[a, Threaded[b, ...]] combines elements for a function f with the attribute Listable.

Examples

Thread addition at lowest level:

{{1, 2}, {3, 4}} + Threaded[{10, 20}]

Specify threading level:

{{1, 2}, {3, 4}} + Threaded[{100, 200}, 1]

Please visit the official Wolfram Language Reference for more details.