Approx. evaluation : evalf approx and Digits

evalf or approx evaluates to a numeric approximation (if possible).
Input :

evalf(sqrt(2))

Output, if in the cas configuration (Cfg menu) Digits=7 (that is hardware floats are used, and 7 digits are displayed) :

1.414214

You can change the number of digits in a commandline by assigning the variable DIGITS or Digits. Input :

DIGITS:=20

evalf(sqrt(2))

Output :

1.4142135623730950488

Input :

evalf(10^-5)

Output :

1e-05

Input :

evalf(10^15)

Output :

1e+15

Input :

evalf(sqrt(2))*10^-5

Output :

1.41421356237e-05