gradio/components/number.py

"""gr.Number() component."""

from __future__ import annotations

from collections.abc import Callable, Sequence
from typing import TYPE_CHECKING, Any

from gradio_client.documentation import document

from gradio.components.base import Component, FormComponent
from gradio.events import Events
from gradio.exceptions import Error

if TYPE_CHECKING:
    from gradio.components import Timer


@document()
class Number(FormComponent):
    """
    Creates a numeric field for user to enter numbers as input or display numeric output.

    Demos: tax_calculator, blocks_simple_squares
    """

    EVENTS = [Events.change, Events.input, Events.submit, Events.focus]

    def __init__(
        self,
        value: float | Callable | None = None,
        *,
        label: str | None = None,
        info: str | None = None,
        every: Timer | float | None = None,
        inputs: Component | Sequence[Component] | set[Component] | None = None,
        show_label: bool | None = None,
        container: bool = True,
        scale: int | None = None,
        min_width: int = 160,
        interactive: bool | None = None,
        visible: bool = True,
        elem_id: str | None = None,
        elem_classes: list[str] | str | None = None,
        render: bool = True,
        key: int | str | None = None,
        precision: int | None = None,
        minimum: float | None = None,
        maximum: float | None = None,
        step: float = 1,
    ):
        """
        Parameters:
            value: default value. If callable, the function will be called whenever the app loads to set the initial value of the component.
            label: the label for this component, displayed above the component if `show_label` is `True` and is also used as the header if there are a table of examples for this component. If None and used in a `gr.Interface`, the label will be the name of the parameter this component corresponds to.
            info: additional component description, appears below the label in smaller font. Supports markdown / HTML syntax.
            every: Continously calls `value` to recalculate it if `value` is a function (has no effect otherwise). Can provide a Timer whose tick resets `value`, or a float that provides the regular interval for the reset Timer.
            inputs: Components that are used as inputs to calculate `value` if `value` is a function (has no effect otherwise). `value` is recalculated any time the inputs change.
            show_label: if True, will display label.
            container: If True, will place the component in a container - providing some extra padding around the border.
            scale: relative size compared to adjacent Components. For example if Components A and B are in a Row, and A has scale=2, and B has scale=1, A will be twice as wide as B. Should be an integer. scale applies in Rows, and to top-level Components in Blocks where fill_height=True.
            min_width: minimum pixel width, will wrap if not sufficient screen space to satisfy this value. If a certain scale value results in this Component being narrower than min_width, the min_width parameter will be respected first.
            interactive: if True, will be editable; if False, editing will be disabled. If not provided, this is inferred based on whether the component is used as an input or output.
            visible: If False, component will be hidden.
            elem_id: An optional string that is assigned as the id of this component in the HTML DOM. Can be used for targeting CSS styles.
            elem_classes: An optional list of strings that are assigned as the classes of this component in the HTML DOM. Can be used for targeting CSS styles.
            render: If False, component will not render be rendered in the Blocks context. Should be used if the intention is to assign event listeners now but render the component later.
            key: if assigned, will be used to assume identity across a re-render. Components that have the same key across a re-render will have their value preserved.
            precision: Precision to round input/output to. If set to 0, will round to nearest integer and convert type to int. If None, no rounding happens.
            minimum: Minimum value. Only applied when component is used as an input. If a user provides a smaller value, a gr.Error exception is raised by the backend.
            maximum: Maximum value. Only applied when component is used as an input. If a user provides a larger value, a gr.Error exception is raised by the backend.
            step: The interval between allowed numbers in the component. Can be used along with optional parameters `minimum` and `maximum` to create a range of legal values starting from `minimum` and incrementing according to this parameter.
        """
        self.precision = precision
        self.minimum = minimum
        self.maximum = maximum
        self.step = step

        super().__init__(
            label=label,
            info=info,
            every=every,
            inputs=inputs,
            show_label=show_label,
            container=container,
            scale=scale,
            min_width=min_width,
            interactive=interactive,
            visible=visible,
            elem_id=elem_id,
            elem_classes=elem_classes,
            render=render,
            key=key,
            value=value,
        )

    @staticmethod
    def _round_to_precision(num: float | int, precision: int | None) -> float | int:
        """
        Round to a given precision.

        If precision is None, no rounding happens. If 0, num is converted to int.

        Parameters:
            num: Number to round.
            precision: Precision to round to.
        Returns:
            rounded number or the original number if precision is None
        """
        if precision is None:
            return num
        elif precision == 0:
            return int(round(num, precision))
        else:
            return round(num, precision)

    def preprocess(self, payload: float | None) -> float | int | None:
        """
        Parameters:
            payload: the field value.
        Returns:
            Passes field value as a `float` or `int` into the function, depending on `precision`.
        """
        if payload is None:
            return None
        elif self.minimum is not None and payload < self.minimum:
            raise Error(f"Value {payload} is less than minimum value {self.minimum}.")
        elif self.maximum is not None and payload > self.maximum:
            raise Error(
                f"Value {payload} is greater than maximum value {self.maximum}."
            )
        return self._round_to_precision(payload, self.precision)

    def postprocess(self, value: float | int | None) -> float | int | None:
        """
        Parameters:
            value: Expects an `int` or `float` returned from the function and sets field value to it.
        Returns:
            The (optionally rounded) field value as a `float` or `int` depending on `precision`.
        """
        if value is None:
            return None
        return self._round_to_precision(value, self.precision)

    def api_info(self) -> dict[str, str]:
        return {"type": "number"}

    def example_payload(self) -> Any:
        return 3

    def example_value(self) -> Any:
        return 3