format compact
a=[1 -4 3 -2]
a =
     1    -4     3    -2
roots(a)
ans =
   3.2695 + 0.0000i
   0.3652 + 0.6916i
   0.3652 - 0.6916i
x=roots(a)
x =
   3.2695 + 0.0000i
   0.3652 + 0.6916i
   0.3652 - 0.6916i
plot(x,'o')
grid
compass(x)
abs(x)
ans =
    3.2695
    0.7821
    0.7821
angle(x)
ans =
         0
    1.0849
   -1.0849
angle(x)*180/pi
ans =
         0
   62.1615
  -62.1615
b=[-1,0,-6,0,1,3,0,0]
b =
  Columns 1 through 6
    -1     0    -6     0     1     3
  Columns 7 through 8
     0     0
b=[-1,0,-6,0,1,3,0,0]
b =
  Columns 1 through 6
    -1     0    -6     0     1     3
  Columns 7 through 8
     0     0
roots(b)
ans =
   0.0000 + 0.0000i
   0.0000 + 0.0000i
   0.0383 + 2.4844i
   0.0383 - 2.4844i
   0.8304 + 0.0000i
  -0.4535 + 0.6160i
  -0.4535 - 0.6160i
plot(ans,'o')
format long e
roots(b)
ans =
      0.000000000000000e+00 + 0.000000000000000e+00i
      0.000000000000000e+00 + 0.000000000000000e+00i
      3.831030889283532e-02 + 2.484432805759941e+00i
      3.831030889283532e-02 - 2.484432805759941e+00i
      8.303899476123050e-01 + 0.000000000000000e+00i
     -4.535052826989876e-01 + 6.160374074801960e-01i
     -4.535052826989876e-01 - 6.160374074801960e-01i
t=[-4:4];
b
b =
  Columns 1 through 6
    -1     0    -6     0     1     3
  Columns 7 through 8
     0     0
polyval(b,t)
ans =
  Columns 1 through 3
       22512        3645         324
  Columns 4 through 6
           9           0          -3
  Columns 7 through 9
        -300       -3591      -22416
plot(t,polyval(b,t),'r*')
tj=linspace(-4,4,1000);
plot(tj,polyval(b,tj))
x=roots(b)
x =
      0.000000000000000e+00 + 0.000000000000000e+00i
      0.000000000000000e+00 + 0.000000000000000e+00i
      3.831030889283532e-02 + 2.484432805759941e+00i
      3.831030889283532e-02 - 2.484432805759941e+00i
      8.303899476123050e-01 + 0.000000000000000e+00i
     -4.535052826989876e-01 + 6.160374074801960e-01i
     -4.535052826989876e-01 - 6.160374074801960e-01i
poly(x)
ans =
  Column 1
     1.000000000000000e+00
  Column 2
    -4.440892098500626e-16
  Column 3
     5.999999999999998e+00
  Column 4
    -3.108624468950438e-15
  Column 5
    -1.000000000000004e+00
  Column 6
    -2.999999999999993e+00
  Column 7
                         0
  Column 8
                         0
format
poly(x)

ans =

  Columns 1 through 4

    1.0000   -0.0000    6.0000   -0.0000

  Columns 5 through 8

   -1.0000   -3.0000         0         0

a

a =

     1    -4     3    -2

b

b =

  Columns 1 through 6

    -1     0    -6     0     1     3

  Columns 7 through 8

     0     0

c=conv(a,b)

c =

  Columns 1 through 6

    -1     4    -9    26   -17    11

  Columns 7 through 11

    -9     7    -6     0     0

deconv(c,b)

ans =

     1    -4     3    -2

[v,z]=deconv(c,b)

v =

     1    -4     3    -2


z =

  Columns 1 through 6

     0     0     0     0     0     0

  Columns 7 through 11

     0     0     0     0     0

prolozeni
prolozeni
koeficienty
    0.0571   -1.1955    8.8070    2.2071

prolozeni
koeficienty
   -0.4250    5.8679    5.0321

prolozeni
[Warning: Polynomial is not unique; degree
>= number of data points.] 
[> In <a href="matlab:matlab.internal.language.introspective.errorDocCallback('polyfit', 'C:\Program Files\matlab\R2019a\toolbox\matlab\polyfun\polyfit.m', 74)" style="font-weight:bold">polyfit</a> (<a href="matlab: opentoline('C:\Program Files\matlab\R2019a\toolbox\matlab\polyfun\polyfit.m',74,0)">line 74</a>)
  In <a href="matlab:matlab.internal.language.introspective.errorDocCallback('prolozeni', 'H:\PPEL_cviceni\PPEL_2019\cv_patek\07_cv\prolozeni.m', 8)" style="font-weight:bold">prolozeni</a> (<a href="matlab: opentoline('H:\PPEL_cviceni\PPEL_2019\cv_patek\07_cv\prolozeni.m',8,0)">line 8</a>)] 
koeficienty
  Columns 1 through 4

   -0.0001    0.0055   -0.0912    0.7441

  Columns 5 through 8

   -3.0665    5.3717         0   -4.5898

  Column 9

   11.6263


stupenPol
Zadej stupen polynomu: 80
Zadej stupen polynomu: -1
Zadej stupen polynomu: 3
stupenPol
Zadej stupen polynomu: 4

VAchar
koeficienty
   -0.0001    0.0076    0.0356   -0.0404

VAchar
koeficienty
   -0.0010    0.2946   -1.2424