simp

Arguments

N, D

real polynomials or real matrix polynomials

H

rational matrix (i.e matrix with entries n/d ,n and d real polynomials)

Description

[n1,d1]=simp(n,d) calculates two polynomials n1 and d1 such that n1/d1 = n/d.

If N and D are polynomial matrices the calculation is performed element-wise.

H1=simp(H) is also valid (each entry of H is simplified in H1).

no threshold is given, i.e. simp cannot forces a simplification. For linear dynamic systems which include integrator(s) simplification changes the static gain. (H(0) for continuous systems or H(1) for discrete systems). For complex data, simp returns its input(s). Rational simplification is called after nearly each operations on rationals. It is possible to toggle simplification on or off using simp_mode function.

Examples

s = poly(0,'s');
[n,d] = simp((s+1)*(s+2),(s+1)*(s-2))

simp_mode(%F); hns = s/s
simp_mode(%T); hns = s/s

See also

• simp_mode — toggle rational simplification
• clean — cleans matrices (round to zero small entries)
• roots — roots of a polynomial
• trfmod — poles and zeros display
• poly — Polynomial definition from given roots or coefficients, or characteristic to a square matrix.