MathFun                 package:base                 R Documentation

Miscellaneous Mathematical Functions

Description:

     These functions compute miscellaneous mathematical functions. The
     naming follows the standard for computer languages such as C or
     Fortran.

Usage:

     abs(x)
     sqrt(x)

Arguments:

       x: a numeric or 'complex' vector or array.

Details:

     These are generic functions: methods can be defined for them
     individually or via the 'Math' group generic.  For complex
     arguments (and the default method), 'z', 'abs(z) == Mod(z)' and
     'sqrt(z) == z^0.5'.

     'abs(x)' returns an 'integer' vector when 'x' is 'integer' or
     'logical'.

S4 methods:

     Both are S4 generic and members of the 'Math' group generic.

References:

     Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) _The New S
     Language_. Wadsworth & Brooks/Cole.

See Also:

     'Arithmetic' for simple, 'log' for logarithmic, 'sin' for
     trigonometric, and 'Special' for special mathematical functions.

     'plotmath' for the use of 'sqrt' in plot annotation.

Examples:

     require(stats) # for spline
     require(graphics)
     xx <- -9:9
     plot(xx, sqrt(abs(xx)),  col = "red")
     lines(spline(xx, sqrt(abs(xx)), n=101), col = "pink")

