# [PD] [OT] "processing" application

Martin Peach martin.peach at sympatico.ca
Sat Oct 14 16:44:28 CEST 2006

```Mathieu Bouchard wrote:
> On Fri, 13 Oct 2006, mark edward grimm wrote:
>
>> What the hell is a 'float' anyway? Can the definition be summed up in
>> a concise paragraph in laymen terminology
>
> It's an integer multiplied by a power of two. That's about as layman
> as it can reasonably get. In Pd the integer is between 2^23 and 2^24
> and the power of two is between 2^-149 and 2^106.
It's not exactly an integer since it's supposed to be a fixed point
number between 1 and just less than 2,  multiplied by a power of two.
The term 'float' is short for 'floating point', which means the number
can have the decimal point anywhere in the number, not just at one
position. In the float the binary point starts out at the left and the
power effectively moves it.
The thing about the laity is that they are free to learn on their own
and can thereby acquire even more knowledge than those who have gone
through the system which only tells them what it wants them to know.

For example this is the representation of the number 1.5 X 2^20 =
1572864 (aka UNITBIT32) in
IEEE Standard 754 Double Precision Storage Format (double):
63        62            52 51               32
31                            0
+--------+----------------+-------------------+------------------------------+
| s 1bit | e[62:52] 11bit | f[51:32] 20bit    | f[31:0]
32bit                |
+--------+----------------+-------------------+------------------------------+
B0-------------->B1---------->B2----->B3----->B4----->B5----->B6----->B7----->
0         10000010011
1000000000000000000000000000000000000000000000000000

Martin

```