why there is a small error in these simple calculations?

3e-4-3*10^-4

 sum=0;
			for i=1:1000
			   sum=sum+0.001;
			end
			sum_output=sum

this gives an answer of -5.421010862427522e-20 and 1.000000000000001

it should be obviously 0 and 1. what happened during the running of program??

[Stephen23]

"it should be obviously 0 and 1. "

Nope. Not with binary floating point numbers.

Search this forum for "floating point" and you will learn the reasons why this happens.

Answer 1

[Star Strider]

See the documentation on Floating-Point Numbers (link).