# Bisection method to find the root

### Description

This function is to apply bisection method to find the root of a function f.

### Usage

1 | ```
my.bisec(f, int.l, int.u, eps = 1e-06)
``` |

### Arguments

`f` |
the function for which the root is sought. |

`int.l` |
a vector containing the lower bound of the interval to be searched for the root. The length of the vector is the same as that of the input of function f. |

`int.u` |
a vector containing the upper bound of the interval to be searched for the root. The length of the vector is the same as that of the input of function f. |

`eps` |
a single value: a threshold to control the convergence criterion. The default is 1e-06. |

### Details

Both int.l and int.u must be specified: the upper bound must be strictly larger than the lower bound.

The function f must be well defined without invalid output(NA, nan, Inf, etc).

The length of the input of function f, the output of function f, int.l and int.u must be the same.

### Value

a vector containing the root of the function. If there is no root in the interval (int.l, int.u), lower bound of the interval will be returned.

### Author(s)

Na You <youn@mail.sysu.edu.cn> and Gongyi Huang<53hgy@163.com>

### References

Na You and Gongyi Huang.(2016) An Empirical Bayes Method for Genotyping and SNP detection Using Multi-sample Next-generation Sequencing Data.

### Examples

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