Decimal output from a simple equation

Question

Let

x= 0.0000000000000000036;

y = 1 - x

If i type this in Mathematica the answer of y is 1. I want the answer to be as it is 0.9999999999999999964

x=1/277777777777777769... or as inexact but showing digits 1 - 0.0000000000000000036`2 — ciao, Jul 05 '14 at 21:31
@rasher. Mathematica rounds it up to unity istead of showing me the answer 0.9999999...64 — Nikolas, Jul 05 '14 at 21:37
If you're on pre- 9.x, you might need to change the "displayed precision" option under "appearance->Formatting" in preferences. Try adding //InputForm to the end of your calculation, see what you see... If you're using N to convert exact to inexact, make sure you specify enough precision in it. — ciao, Jul 05 '14 at 21:44
@rasher. Neither work. I set the displayed precision to 20decimal and still the same. Also //InputForm does not change anything — Nikolas, Jul 05 '14 at 21:48

score 2 · Answer 1 · answered Jul 05 '14 at 21:50

2

    x = SetPrecision[0.0000000000000000036, 1];
    y = 1 - x

(*0.9999999999999999964*)

answered Jul 05 '14 at 21:50

Basheer Algohi

Works Great! thanks :) – Nikolas Jul 05 '14 at 21:55
1

with little less typing "x =0.0000000000000000036`1"; – Nasser Jul 05 '14 at 22:00
@Nasser. It is not my code. It is a part of it and the number comes from other equations and changing variables. I simplified the question. – Nikolas Jul 05 '14 at 22:03

Bob Hanlon · Answer 2 · 2014-07-06T15:01:25.073

2

Amplifying on Algohi's answer

Table[{
   x = SetPrecision[0.0000000000000000036, n],
   Precision[x],
   1 - x,
   Precision[1 - x]},
  {n, 10}] // Grid

enter image description here

edited Jul 06 '14 at 15:01

answered Jul 06 '14 at 00:47

Bob Hanlon

2 Answers2