◆ r1mach()

float r1mach ( int i )

Machine parameters (single precision floating-point values)

Purpose: Determines the single precision floating-point machine parameters.

Returns: The value specified by i. (0 will be returned if i is invalid.)

Parameters

[in] i Specifies the value to be returned.
= 1: B^(L-1), the smallest positive magnitude.
= 2: B^U*(1 - B^(-t)), the largest magnitude.
= 3: B^(-t), the smallest relative spacing.
= 4: B^(1-t), the largest relative spacing.
= 5: log10(B)

Note: Assume floating-point numbers are represented in the t-digit, base-B form
sign (B^e)*((x(1)/B) + ... + (x(t)/B^t))
where 0 <= x(i) < B for i = 1, ..., t, 0 < x(1), and L <= e <= U. The values of B, t, L and U are provided in i1mach().

Reference: SLATEC