Usage steps:¡@

(1) The R project website for free download is

(2) R project is free to download at following URLs. Choose one of links
      which closes to your location.

(3) Based on operation system, you can choose Linux, MacOS X or Windows.

(4) For example, download for Windows and the first time to install R

(5) Download the R-code (F81.txt, F84.txt, HKY85.txt, TN93.txt) from¡@

(6) Download data example from

(7) Open the R program ¡@

(8) Before you run the R-code (F81.txt, F84.txt, HKY85.txt, TN93.txt),
      you need to install R packages.The following are the steps to install R packages.
      1. Choose ¡§Packages¡¨ and ¡§Install package(s)¡K¡¨.


¡@    2. And then choose your country.

      3. Now choose which package you want to install. And in this
          example you need to install the package ¡§seqinr¡¨.

(9) Now we use F81.txt for the example. And the processes for the other
      three R-codes are the same. Type ¡¨source("D:/F81.txt") ¡§ on R window.
      In parentheses you can change the route where you save the R-code (F81.txt).

(10) Load the data of the two sequences and set the name for them.

(11)  F81 is a function with two parameters (seq1, seq2), which is in the
         form of ¡§F81 ( seq1, seq2)¡¨. "seq1" and "seq2" are the read data of the
         two sequences, such as x1 and x2 in step 10.