Maxima Function
multi_elem (l_elem, multi_pc, l_var)
decomposes a multi-symmetric polynomial in the multi-contracted form multi_pc in the groups of variables contained in the list of lists l_var in terms of the elementary symmetric functions contained in l_elem.
(%i1) multi_elem ([[2, e1, e2], [2, f1, f2]], a*x + a^2 + x^3, [[x, y], [a, b]]); 3 (%o1) - 2 f2 + f1 (f1 + e1) - 3 e1 e2 + e1 (%i2) ratsimp (%); 2 3 (%o2) - 2 f2 + f1 + e1 f1 - 3 e1 e2 + e1
Other functions for changing bases: comp2ele
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