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polyval | Examples See Also |

y = polyval(p,x) [y,delta] = polyval(p,x,S)

```
y = polyval(p,x)
```

returns the value of the polynomial `p`

evaluated at `x`

. Polynomial `p`

is a vector whose elements are the coefficients of a polynomial in descending powers.
`x`

can be a matrix or a vector. In either case, `polyval `

evaluates `p`

at each element of `x`

.
```
[y,delta] = polyval(p,x,S)
```

uses the optional output structure `S`

generated by `polyfit`

to generate error estimates, `y`

±`delta`

. If the errors in the data input to `polyfit`

are independent normal with constant variance, `y`

±`delta`

contains at least 50% of the predictions.
The `polyvalm(p,x)`

function, with `x`

a matrix, evaluates the polynomial in a matrix sense. See `polyvalm`

for more information.
The polynomialis evaluated at x = 5, 7, and 9 with
p = [3 2 1]; polyval(p,[5 7 9])which results in

ans = 86 162 262For another example, see

`polyfit`

`polyfit`

` `

Polynomial curve fitting
`polyvalm`

` `

Matrix polynomial evaluation