Name

Description

There are two basic types, variables and constants.

The variables are one of:

    a - count of bits on in fp1, not on in fp2
    b - count of bits on in fp2, not on in fp1
    c - count of bits on in both fp1 and fp2
    d - count of bits off in both fp1 and fp2

Constants are always double-precision numbers expressed as either a whole number or a decimal number (exponent notation is not supported). Examples include: 1, 1.0, 1.00004, 243.333.

Unary Operators are (x refers to any valid subexpression):

-x       Negation
sqrt(x)  Square root

Binary Operators are (x1 and x2 refer to valid subexpressions):

    x1+x2       Addition
    x1-x2       Subtraction
    x1*x2       Multiplication
    x1/x2       Division
    x1^x2       Raise x1 to the x2 power
    min(x1,x2)  Minimum
    max(x1,x2)  Maximum

Parentheses are used to modify operator association (left-to-right) and precedence from the default:

    -       Unary negation
    ^       Exponentiation
    *, /    Multiplication/division
    +, -    Binary addition/subtraction

In addition to the above, the expression evaluator recognizes the following built-in named expressions:

    TANIMOTO         -  c/(a+b+c)
    EUCLID           -  sqrt((c+d)/(a+b+c+d))
    DICE             -  (2.0*c)/((a+c)+(b+c))
    COSINE           -  c/sqrt((a+c)*(b+c))
    KULCZYNSKI       -  0.5*((c/(a+c))+(c/(b+c)))
    JACCARD          -  c/(a+b+c)
    RUSSELL/RAO      -  c/(a+b+c+d)
    MATCHING         -  (c+d)/(a+b+c+d)
    HAMMAN           -  ((c+d)-(a+b))/(a+b+c+d)
    ROGERS/TANIMOTO  -  (c+d)/((a+b)+(a+b+c+d))
    FORBES           -  (c*(a+b+c+d))/((a+c)*(b+c))
    SIMPSON          -  c/min((a+c),(b+c))
    PEARSON          -  (c*d-a*b)/sqrt((a+c)*(b+c)*(a+d)*(b+d))
    YULE             -  (c*d-a*b)/(c*d+a*b)
    MAHNATTAN        -  (a+b)/(a+b+c+d)

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