r̲e̲a̲l̲ p̲r̲o̲c̲e̲d̲u̲r̲e̲ EXPC(a, b, c, d); v̲a̲l̲u̲e̲ a, b; r̲e̲a̲l̲ a, b, c, d; c̲o̲m̲m̲e̲n̲t̲ ; b̲e̲g̲i̲n̲ c := exp(a); d := c × sin(b); c := c × cos(b) e̲n̲d̲ EXPC;