# secant: A function to find roots of univariate functions. In OOmisc: Ozgur-Ozlem Miscellaneous

## Description

Finds the roots of univariate functions by using the Secant method.

## Usage

 `1` ```secant(fun, x0, x1, eps, maxit = 20, silent = FALSE) ```

## Arguments

 `fun` a function for which the root is searched. `x0` a numeric value to be used to start the algorithm (first initial). `x1` a numeric value to be used to start the algorithm (second initial). `eps` a numeric value to be considered as the tolerance for convergence of the algorithm. `maxit` a numeric value which denotes maximum number of iterations to be consumed. `silent` a logical statement which decides whether the iterations should be printed.

## Value

Returns a numeric result.

## Author(s)

Ozlem Ilk, Ozgur Asar

## References

Ilk, O. (2011). R Yazilimina Giris [Introduction to R Language]. ODTU Yayincilik [METU Press].

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16``` ```## Example-1 f1=function(x) x^3+sqrt(x)-1 secant(f1,0.5,0.55,10^-10,silent=FALSE) ## Example-2 f2=function(x) x^3-sinh(x)+4*x^2+6*x+9 # searching for reasonable initials x0=seq(-10,10,,100) plot(x0,f2(x0),type="n") lines(x0,f2(x0)) x0=seq(6,8,,100) plot(x0,f2(x0),type="n") lines(x0,f2(x0)) abline(h=0,lty=2) secant(f2,7,7.2,10^-10,maxit=30,silent=FALSE) ```

### Example output

```Iterasyon: 1 , Result= 0.610619
Iterasyon: 2 , Result= 0.6051663
Iterasyon: 3 , Result= 0.6054222
Iterasyon: 4 , Result= 0.6054234
Iterasyon: 5 , Result= 0.6054234
Solution: 0.6054234
[1] 0.6054234
Iterasyon: 1 , Result= 7.106078
Iterasyon: 2 , Result= 7.112647
Iterasyon: 3 , Result= 7.113065
Iterasyon: 4 , Result= 7.113063
Iterasyon: 5 , Result= 7.113063
Solution: 7.113063
[1] 7.113063
```

OOmisc documentation built on May 1, 2019, 10:17 p.m.