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Solving A Symmetric Toeplitz System Using Levinson's Algorithm
 Syntax `levinson(`r`, `b`)` See Also toeplitz , tridiag , matrix division

Description
Uses Levinson's algorithm to solve the equation `T x = b` for `x`, where `T` is the Toeplitz matrix defined by ```             /  1        if i = j      T   = {       i,j   \  r        otherwise                 |i - j| ```The column vectors r and b must be real or double-precision and have the same length. The return value has the same number of rows as b and is real, if both b and r are real and double-precision otherwise.

Example
The following is a Toeplitz system of equations: ```      / 1  .5 \ / x  \    / 1 \      |       | |  1 |  = |   |      |       | |    |    |   |      \ .5  1 / \ x  /    \ 2 /                   2 ```If you enter ```      r = {.5d0, .25}      b = {1.d0, 2.}      levinson(r, b) ``` O-Matrix will respond ```      {      0      2      } ``` which is the value of the vector `x` that solves the equation above. Note that the vectors r and b must be of the same length even though the last component of r is not used.