Fixed-Point Toolbox™

quantize - Apply `quantizer` object to data

Syntax

y = quantize(q, x) [y1,y2,...] = quantize(q,x1,x2,...)

Description

y = quantize(q, x) uses the quantizer object q to quantize x. When x is a numeric array, each element of x is quantized. When x is a cell array, each numeric element of the cell array is quantized. When x is a structure, each numeric field of x is quantized. Quantize does not change nonnumeric elements or fields of x, nor does it issue warnings for nonnumeric values. The output y is a built-in double. When the input x is a structure or cell array, the fields of y are built-in doubles.

[y1,y2,...] = quantize(q,x1,x2,...) is equivalent to

y1 = quantize(q,x1), y2 = quantize(q,x2),...

The quantizer object states

max — Maximum value before quantizing
min — Minimum value before quantizing
noverflows — Number of overflows
nunderflows — Number of underflows
noperations — Number of quantization operations

are updated during the call to quantize, and running totals are kept until a call to resetlog is made.

Examples

The following examples demonstrate using quantize to quantize data.

Example 1 - Custom Precision Floating-Point

The code listed here produces the plot shown in the following figure.

u=linspace(-15,15,1000);
q=quantizer([6 3],'float');
range(q)

ans =

   -14    14
y=quantize(q,u);
plot(u,y);title(tostring(q))

Warning: 68 overflows.

Example 2 - Fixed-Point