not a polynomial error

Hey Guys,

I've a problem with using command SymNum. It returns :

Error using sym/sym2poly (line 30)
Not a polynomial.

Error in blaab (line 148)
TFnum = sym2poly(symNum);   

I'm trying to return a eigenvalue to polynomial value in order to take frequency response from eigenvalues.

here are my two eigenvalues and I found a " ^(1/2) " or sqrt in my eigenvalues and I'm sure bc of sqrt I become this error but does anyone know how shoud I solve this problem??

d =
  (1000*(300*(915166350000000000000000000000000000*s + 92091374302500000000000000000000000*s^2 + 4050759037830375000000000000000000*s^3 + 85294453297221250000000000000000*s^4 + 839426647542151875000000000000*s^5 + 3201446226471423890625000000*s^6 + 1160530083851214375000000*s^7 + 274295745577856250000*s^8 + 31391692074000000*s^9 + 2318919840000*s^10 + 78804495000000000000000000000*s^3*pi^2 + 8046264822750000000000000000*s^4*pi^2 + 152665574748412500000000000*s^5*pi^2 + 1038770004137420625000000*s^6*pi^2 + 2546901356286937500000*s^7*pi^2 - 3274156852736625625*s^8*pi^2 - 2383290277254600*s^9*pi^2 - 552158796114*s^10*pi^2 - 54962280*s^11*pi^2 - 2025*s^12*pi^2 + 3223820250000000000000000000000000000)^(1/2) - 50121000000000000000*s - 1276263150000000000*s^2 - 7471084987500000*s^3 + 31693412750000*s^4 + 10773802575*s^5 + 1832076*s^6 + 135*s^7 - 538650000000000000000))/(1013760000000000000000000*s + 21237684000000000000000*s^2 + 165999060600000000000*s^3 + 566102834000000000*s^4 + 204318183000000*s^5 + 48091927725*s^6 + 5496228*s^7 + 405*s^8 + 3950100000000000000*s^2*pi^2 + 43953030000000000*s^3*pi^2 + 192919277250000*s^4*pi^2 + 54962280000*s^5*pi^2 + 4050000*s^6*pi^2 + 15800400000000000000000000)
 -(1000*(50121000000000000000*s + 300*(915166350000000000000000000000000000*s + 92091374302500000000000000000000000*s^2 + 4050759037830375000000000000000000*s^3 + 85294453297221250000000000000000*s^4 + 839426647542151875000000000000*s^5 + 3201446226471423890625000000*s^6 + 1160530083851214375000000*s^7 + 274295745577856250000*s^8 + 31391692074000000*s^9 + 2318919840000*s^10 + 78804495000000000000000000000*s^3*pi^2 + 8046264822750000000000000000*s^4*pi^2 + 152665574748412500000000000*s^5*pi^2 + 1038770004137420625000000*s^6*pi^2 + 2546901356286937500000*s^7*pi^2 - 3274156852736625625*s^8*pi^2 - 2383290277254600*s^9*pi^2 - 552158796114*s^10*pi^2 - 54962280*s^11*pi^2 - 2025*s^12*pi^2 + 3223820250000000000000000000000000000)^(1/2) + 1276263150000000000*s^2 + 7471084987500000*s^3 - 31693412750000*s^4 - 10773802575*s^5 - 1832076*s^6 - 135*s^7 + 538650000000000000000))/(1013760000000000000000000*s + 21237684000000000000000*s^2 + 165999060600000000000*s^3 + 566102834000000000*s^4 + 204318183000000*s^5 + 48091927725*s^6 + 5496228*s^7 + 405*s^8 + 3950100000000000000*s^2*pi^2 + 43953030000000000*s^3*pi^2 + 192919277250000*s^4*pi^2 + 54962280000*s^5*pi^2 + 4050000*s^6*pi^2 + 15800400000000000000000000)
 

thx.

[语桐 李]

Hello,I had the same problem, have you solved this problem? Thanks!