Polynomials, MATLAB in Statistics

Polynomials:

Simple curves are polynomials of various degrees, or orders. The degree is the integer of the highest exponent in the expression. The illustrations are as follows:

  • A straight line is the first order or degree 1 polynomial of the form ax + b, or more clearly ax1+ b.
  • A quadratic is a second order (or degree 2) polynomial of the form ax2 + bx + c.
  • A cubic (degree 3) is of the form ax3 + bx2 + cx + d.

A MATLAB represents a polynomial as a row vector of coefficients. For illustration, the polynomial x3 + 2x2 - 4x + 3 would be represented by the vector [1 2 -4 3].

The polynomial 2x4 - x2 + 5 would be represented by [2 0 -1 0 5]; note that the zero terms for x3 and x1.

There are built-in functions sym2poly and poly2sym which convert symbolic expressions to polynomial vectors and vice versa, the illustration is as shown below:

>> myp = [1,2,-4,3];

>> poly2sym(myp)

ans =

x^3+2*x^2-4*x+3

>> mypoly = [2 0 -1 0 5];

>> poly2sym(mypoly)

ans =

2*x^4-x^2+5

>> sym2poly(ans)

ans =

2 0 -1 0 5

Posted Date: 10/22/2012 8:40:45 AM | Location : United States







Related Discussions:- Polynomials, Assignment Help, Ask Question on Polynomials, Get Answer, Expert's Help, Polynomials Discussions

Write discussion on Polynomials
Your posts are moderated
Related Questions
Index vector: The index vector is then used as the indices for original vector. To get grades vector in ascending order, the indices used would be grades (2), grades (5), and

Sorting Strings: For the matrix of strings, the sort function works exactly as formerly for numbers. For illustration, >> words = char('Hi', 'Hello', 'Howdy', 'Goodbye', '

Example of sorting strings: To sort a cell array of strings, also the sort function is used. The illustration is as follows, >> engcellnames = {'Chemical','Mechanical',.

Combining Nested FOR Loops and the IF Statements: The statements inside a nested loop can be any of the valid statement, involving any selection statement. For e.g., there can

Function polyval - interpolation: The function polyval can then be used to compute the polynomial at particular values. For illustration, we could compute at every value in th

Advanced File Input and Output: In that section, we saw how to read the values entered by user using the input as well as the output functions disp and fprintf, that shows inf

Illustration of Nested loops: Running the script shows the output: >> printstars ***** ***** ***** The variable rows identifies the number of rows to print, and

Illustration of Input in a for loop: In this illustration, the loop variable iv iterates through the values 1 through 3, therefore the action is repeated three times. The acti

Nested Functions: We have seen that the loops can be nested, that means that one inside of the other, functions can be nested. The terminology for nested functions is that an

Illustration of Input in a for loop: In this illustration, the loop variable iv iterates through the values 1 through 3, therefore the action is repeated three times. The acti