# maxlog

## Syntax

```y = maxlog(a) y = maxlog(q) ```

## Description

`y = maxlog(a)` returns the largest real-world value of `fi` object `a` since logging was turned on or since the last time the log was reset for the object.

Turn on logging by setting the `fipref` object `LoggingMode` property to `on`. Reset logging for a `fi` object using the `resetlog` function.

`y = maxlog(q)` is the maximum value after quantization during a call to `quantize(q,...)` for `quantizer` object `q`. This value is the maximum value encountered over successive calls to `quantize` since logging was turned on, and is reset with `resetlog(q)`. `maxlog(q)` is equivalent to `get(q,'maxlog')` and `q.maxlog`.

## Examples

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1. ```P = fipref('LoggingMode','on'); format long g a = fi([-1.5 eps 0.5], true, 16, 15); a(1) = 3.0; maxlog(a)```
```Warning: 1 overflow(s) occurred in the fi assignment operation. > In embedded.fi/fifactory In fi (line 226) Warning: 1 underflow(s) occurred in the fi assignment operation. > In embedded.fi/fifactory In fi (line 226) Warning: 1 overflow(s) occurred in the fi assignment operation. ans = 0.999969482421875```

The largest value `maxlog` can return is the maximum representable value of its input. In this example, `a` is a signed `fi` object with word length `16`, fraction length `15` and range:

 -1 ≤ x ≤ 1 – 2-15 (1)

2. You can obtain the numerical range of any `fi` object `a` using the `range` function:

```format long g r = range(a)```
```r = -1 0.999969482421875 DataTypeMode: Fixed-point: binary point scaling Signedness: Signed WordLength: 16 FractionLength: 15```
1. ```q = quantizer; warning on format long g x = [-20:10]; y = quantize(q,x); maxlog(q)```
```Warning: 29 overflow(s) occurred in the fi quantize operation. > In embedded.quantizer/quantize (line 81) ans = 0.999969482421875```

The largest value `maxlog` can return is the maximum representable value of its input.

2. You can obtain the range of `x` after quantization using the `range` function:

```format long g r = range(q)```
```r = -1 0.999969482421875``` 