# Up Day (UPDAY)

> QuantNexus indicator page for positive session movement.

**Route**: `/quantnexus/indicators/upday/`

## What It Does

UPDAY measures upward price movement over the selected lookback window.

## Formula

`Up Day = max(close - previous close, 0)`

## Parameters

- `period` - default `14`

## C++23 API

```cpp
#include <nonabt/indicators/upday.hpp>
auto upDay = std::make_unique<nonabt::UPDAY>(data().close(), 14);
```

## Common Usage

- Use it to isolate positive movement in a trend study.
- Pair it with down-move logic for directional comparisons.
- Helpful as an input to momentum or breadth calculations.