MATLAB Programming Fundamentals - MathWorks

Create Custom Tolerance

This example shows how to create a custom tolerance to determine if two DNA sequences

have a Hamming distance within a specified tolerance. For two DNA sequences of the

same length, the Hamming distance is the number of positions in which the nucleotides

(letters) of one sequence differ from the other.

In a file, DNA.m, in your working folder, create a simple class for a DNA sequence.

classdef DNA

properties(SetAccess=immutable)

Sequence

end

methods

function dna = DNA(sequence)

validLetters = ...

sequence == 'A' | ...

sequence == 'C' | ...

sequence == 'T' | ...

sequence == 'G';

if ~all(validLetters(:))

error('Sequence contained a letter not found in DNA.')

end

dna.Sequence = sequence;

end

end

end

In a file in your working folder, create a tolerance class so that you can test that DNA

sequences are within a specified Hamming distance. The constructor requires a Value

property that defines the maximum Hamming distance.

classdef HammingDistance < matlab.unittest.constraints.Tolerance

properties

Value

end

methods

function tolerance = HammingDistance(value)

tolerance.Value = value;

end

33 Unit Testing