round numeric 0

Hi everyone! I have a matrix like this:

   A=[ 1 , .3*10^-8 , .2*10^-8 , .2*10^-8;
       . 3*10^-8; 1; .2*10^-8;
       .2*10^-8, .2*10^-8, 1];

I want 0 (real or integer) where i have a very very very small value. How can I do it?

I know I can use logical mask

A(A<10^-7=0)

but i'm looking for a matlab function that can do automatically. This is a typical numeric problem...

Thanks a lot for you answer.

Pippo

Answer 1

[Andreas Goser]

This is actually done automatically if it is very very very small. But it looks the veryveryvery is different for you. The

eps
Function return what MATLAB sees as small enough to be rounded to zero.

Besides your own suggestion (probably think also of negative small values, you may use all kinds of rounding and formatting like

round
sprintf

depending on your needs.

Answer 2

[Jaap]

your best option:

A(A<small_value) = 0

you can also try:

A = A(bsxfun(@lt,A,1E-7))

I doubt its quicker.

[Jaap]

you get the point