zpk2tf
zpk2tf(z, p, k)
Try it yourself:
| $1 | 
                     zpk2tf([1, 2], [-1, -2], 1)
                         
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| $2 | 
                     zpk2tf([1, 2], [-1, -2])
                         
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| $3 | 
                     zpk2tf([1 - 3i, 2 + 2i], [-1, -2])
                         
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