This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.

# N

 N[expr]gives the numerical value of expr. N[expr, n]attempts to give a result with n-digit precision.
• Unless numbers in expr are exact, or of sufficiently high precision, N[expr, n] may not be able to give results with n-digit precision.
• N[expr, n] may internally do computations to more than n digits of precision.
• \$MaxExtraPrecision specifies the maximum number of extra digits of precision that will ever be used internally.
• The precision n is given in decimal digits; it need not be an integer.
• N[0] gives the number 0. with machine precision.
• N converts each successive argument of any function it encounters to numerical form, unless the head of the function has an attribute such as NHoldAll.
• You can define numerical values of functions using N[f[args]]:=value and N[f[args], n]:=value.
• N[expr, {p, a}] attempts to generate a result with precision at most p and accuracy at most a.
• N[expr, {Infinity, a}] attempts to generate a result with accuracy a.
• N[expr, {Infinity, 1}] attempts to find a numerical approximation to the integer part of expr.
Evaluate numerically:
 Out[1]=

Evaluate numerically to 50-digit precision:
 Out[1]=

With machine-precision input, the results are always machine precision:
 Out[1]=
With exact input, the results can be to the precision specified:
 Out[2]=
 Scope   (20)