El error relativo de una medida es el cociente entre el error absoluto de la medida y el valor real de ésta.
> format long
>> x1=123.7639987;
>> x1
x1 = 123.763998700000
>> format short
>> x2=123.7639987;
>> x2
x2 = 123.76
>> format long e
>> x3=123.7639987;
>> x3
x3 = 1.23763998700000e+002
>> format short e
>> x4=123.7639987;
>> x4
x4 = 1.2376e+002
otro ejemplo
>> format long
>> x5=0.00038746534;
>> x5
x5 = 3.87465340000000e-004
>> format short
>> x6= 0.00038746534;
>> x6
x6 = 3.8747e-004
>> format long e
>> x7=0.00038746534;
>> x7
x7 = 3.87465340000000e-004
>> format short e
>> x8=0.00038746534;
>> x8
x8 = 3.8747e-004
>> output_precision(12)
>> x
x = -5.00000000000e+001
>> x
x = -5.00000000000e+001
>> output_precision(12)
>> x4
x4 = 1.23763998700e+002
>> output_precision(20)
>> x4
x4 = 1.2376399870000000192e+002
>> realmax
ans = 1.7976931348623157081e+308
>> realmin
ans = 2.2250738585072013831e-308
TAREA
>> x=3
x = 3
>> y=5
y = 5
>> z=-6
z = -6
>> M=abs(x)
M = 3
>> L=abs(y)
L = 5
>> G=abs(z)
G = 6
>> A=sum(M+L+G)/3
A = 4.6667
>> F=(y-A)/L
F = 0.066667