1550078481-Ordinary_Differential_Equations__Roberts_

502 Ordinary Differential Equations

iii POLYRTS 181!1 £i

POLYRTS finds all zeros of a polynomial with complex coefficients of degree N where 1 <= N <= 10

Enter the degree of the polynomial N = j4 (Alter you have entered lhe value of N. press lhe Enter key.)

Te1m

••

•• 3

•2

•• 1

•• 0

-·-·-!l!~.f~E_!_!'._~g:.!~I.L9L..!~~_!!ll<!!!_q~,cA.•--~.m_. _____ _1

COEFFICIENTS

(Enter non·zero coelfrcienls.) DECREE REAL PART IMAGINARY PART

Z. OOOOOOEtOO 0. OOOOOOE+OO

Real Part Imaginary Part -3. OOOOOOE+OO 0. OOOOOOE+OO

• l. 300000Et0 1 0. OOOOOOE+OO
  3. ?OOOOORtOl O. OOOOOOEtOO
  .3 -l. SOOOOOE+Ol 0. OOOOOOE+OO
  -13 THE ZEROS OF THIS POLYNOMIAL ARE
  37
  ·15 ZERO REAL PART IMAGINARY PART

5. OOOOOOE-01 -l. 60305 2 E-15
   -3. OOOOOOE+OO 2. 00401SE-16
   2. OOOOOOE+OO -l. OOOOOOEtOO
   2. OOOOOOEtOO l. OOOOOOB+OO

11ND THE ROOTS OF ANOTHER POL YNOM!AL OF DEGREE 4

11ND THE ROOTS OF A POLYNOMIAL OF DIFFERENT DEGREE

Figure A.4 Screen Showing Coefficients and Roots

of a Fourth Degree Polynomial

On the right-hand side of Figure A.4, the coefficients of the polynomial and
the roots of the polynomial appear in single precision, exponential form. Since
-l.603852E-15 is nearly 0 and small compared to 5.000000E-01 = 1/2, one
root of the polynomial is 1/2. And since 2.004815E- 16 is nearly 0 and small
compared to -3, a second root is -3. The other roots are 2 - i and 2 + i. By
clicking on the button FIND THE ROOTS OF ANOTHER POLYNOMIAL
OF DEGREE 4, we can find the roots of another fourth degree polynomial by
entering only the new coefficients- that is , we do not need to enter the degree
of the polynomial again. By clicking on the button FIND THE ROOTS OF
A POLYNOMIAL OF A DIFFERENT DEGREE, we can find the roots of
another polynomial. By clicking on the box in the upper right-hand corner
of the monitor with an X in it, we can exit to the program selection screen
(Figure A.l) which will allow us to run a different program in CSODE or to
exit CSODE.