HP 40gs, error in calculator?

[toml_12953]

(11-03-2017 09:37 PM)pier4r Wrote:  interesting the difference

sin(pi)
-1.158028306006248917735787454453501 E-34 WP-34S in "double mode"
-1.158028306006248941790250554076922 E-34 DM_42 with SHOW

I would have expected way more equal digits.

Maybe Thomas, Paul, Marcus, Walter, Dieter or Gerson (and I forget many) could explain why this difference.

It looks like one of them is using double precision mode to give 16-17 digits of precision. The DM-42 uses Intel's Decimal Floating-Point Math Library which conforms to the IEEE 754-2008 Decimal Floating-Point Arithmetic specification and uses quadruple-precision floating-point format (34.02 decimal digits.) What does the WP-34S use?