Hi,

I have an input like 0.02, and I check in LAMMPS it looks like 0.020000000000156. How to define exactly 0.02?

How to “round” with 3 numbers or 4 numbers after floating point?
Hi,
I have an input like 0.02, and I check in LAMMPS it looks like 0.020000000000156. How to define exactly 0.02?
How to “round” with 3 numbers or 4 numbers after floating point?
What Every Computer Scientist Should Know About FloatingPoint Arithmetic:
https://docs.oracle.com/cd/E1995701/8063568/ncg_goldberg.html
You'll also find original pdf and reprints on the www.
Tomasz
What Every Computer Scientist Should Know About FloatingPoint Arithmetic:
What Every Computer Scientist Should Know About FloatingPoint Arithmetic
You'll also find original pdf and reprints on the www.
that document may be a little bit over the top and is primarily
addressed at "*computer* scientists" and not so much "*computational*
scientists"
the topic of floating point semantics and accuracy is often topic of
lectures at HPC workshops for computational scientists, and there
matters are presented in a much more simplified fashion. a recent
version of my lecture on the topic is posted here:
the short, short version is: a number like 0.02 simply *cannot* be
represented exactly with IEEE754 floating point math (which is what
CPUs are using these days).
axel.