Quote Originally Posted by szlamany
You must be kidding

Bottom line is that double only stores 16 digits - single stores 8. The storage format also allows for the "exponent" placement. All other digits are zero.

When the number is displayed it's not the true figure.

You might have float 3.99999999 and it's displayed as 4!!!!You cannot look at the value visually - it's not going to tell the truth!
I have no way to understand the lengthy paragraphs you quoted. But I fully aware of your own comments above.

I know about 16 digits so I formatted all numbers up to that (if I was not wrong on counting).

I know very well the case of 3.99999999... and 4. But 2 Double values with the same display format, if they are equal, all display digits must be matched.
Am I wrong? Look again at d and w in your case.