Casting to Single in MATLAB

What causes a call typecastin MATLAB?

y=typecast(x,'single');

what does it mean? When I run typecast(3,'single'), it gives 0 2.1250.

I don’t understand what it is.

I am trying to convert this to Java, how can I do this?

In the MATLAB manual:

single - Convert to single precision

Syntax

B = single(A)

Description

B = single(A)converts matrix A to uniform precision, returning this value to B. A can be any numerical object (for example, double). If A is already single precision, the single has no effect. Unit values ​​require less storage than double precision amounts, but have less accuracy and a smaller range.