How to calculate the value of polynomial value for 150 coefficient.It is not possible to use polyval function.

I try this

 for k=1:150
    x=x1(k);   
   fprintf('============')
      sum1=0;
    b=0;
   for i=1:2     
         b=b+B1(i)*power(x,i) ;
         sum1=sum1+b;  
        end
  final(i)=10000+sum1;  
 end

Answer 1

[Walter Roberson]

final = 10000 + B1(1) * x1(1:150) + B1(2) * x1(1:150).^2 ;

This can be written as

   final = 10000 + B1(1) * x1 + B1(2) * x1.^2 ;

if x1 is exactly 150 items long.

[YOGESHWARI PATEL]

No its not working.for example i am having coefficient 1,2,3,4,5,6,7,8,10.so according to it will have polynomial of degree 9.so how to calculate the value of polynomial of degree 150 for different value of x.And i am using MATLAB verion 2013.

[Walter Roberson]

Your sample code is written to evaluate a polynomial of degree 2 at 150 different points. If you want a polynomial of degree 149 or 150 then what is the "for i" doing there?

[Walter Roberson]

Why do you say that polyval will not work?

abc = rand(1,150);
x = randn();
polyval(abc, x)

[John D'Errico]

It will "work". It will produce complete garbage. But that is a completely different issue, as you well know.

[Walter Roberson]

Yep. And unless the user happens to have pure integer coefficients and pure integer x values, it is not clear that they could meaningfully get anything other than garbage (at least not with less than 1800 decimal places results.)