Mon Feb 24 07:57:57 2020 

d1mach_test
  R version 3.4.4 (2018-03-15) 
  d1mach(i) evaluates the i-th machine constant.
  associated with real double precision computer arithmetic.

  Assume that double precision numbers are stored
  with a mantissa of T digits in base B, with an
  exponent whose value must lie between EMIN and EMAX.

  For input arguments of 1 <= I <= 5,
  D1MACH will return the following values:

  D1MACH(1) = B^(EMIN-1), smallest positive magnitude =  1.797693e+308 
  D1MACH(2) = B^EMAX*(1-B^(-T)), the largest magnitude =  2.225074e-308 
  D1MACH(3) = B^(-T), the smallest relative spacing =  1.110223e-16 
  D1MACH(4) = B^(1-T), the largest relative spacing =  2.220446e-16 
  D1MACH(5) = log10(B) =  0.30103