sentences:  In addition, an example code for an LCP solution of a 2D linear elastic contact mechanics problem has also been made public at MATLAB file exchange by Almqvist et al.When two bodies with rough surfaces are pressed against each other, the true contact area formed between the two bodies, formula_91, is much smaller than the apparent or nominal contact area formula_92.The mechanics of contacting rough surfaces are discussed in terms of normal contact mechanics and static frictional interactions.