surrealml-core 0.1.12

//! The functionality and parameters around a clipping normaliser.
use super::traits::Normaliser;

/// A clipping normaliser.
///
/// # Fields
/// * `min` - The minimum value to clip to.
/// * `max` - The maximum value to clip to.
#[derive(Debug, PartialEq)]
pub struct Clipping {
	pub min: Option<f32>,
	pub max: Option<f32>,
}

impl Normaliser for Clipping {
	/// Normalises a value.
	///
	/// # Arguments
	/// * `input` - The value to normalise.
	///
	/// # Returns
	/// The normalised value.
	fn normalise(&self, input: f32) -> f32 {
		match (self.min, self.max) {
			(Some(min), Some(max)) => {
				if input < min {
					min
				} else if input > max {
					max
				} else {
					input
				}
			}
			(Some(min), None) => {
				if input < min {
					min
				} else {
					input
				}
			}
			(None, Some(max)) => {
				if input > max {
					max
				} else {
					input
				}
			}
			(None, None) => input,
		}
	}

	fn key() -> String {
		"clipping".to_string()
	}
}

#[cfg(test)]
mod tests {

	use super::*;

	#[test]
	fn test_normalise_with_both_bounds() {
		let normaliser = Clipping {
			min: Some(0.0),
			max: Some(1.0),
		};
		let input = 0.5;
		let expected = 0.5;
		let actual = normaliser.normalise(input);
		assert_eq!(expected, actual);
	}

	#[test]
	fn test_normalise_with_min_bound() {
		let normaliser = Clipping {
			min: Some(0.0),
			max: None,
		};
		let input = -0.5;
		let expected = 0.0;
		let actual = normaliser.normalise(input);
		assert_eq!(expected, actual);
	}

	#[test]
	fn test_normalise_with_max_bound() {
		let normaliser = Clipping {
			min: None,
			max: Some(1.0),
		};
		let input = 1.5;
		let expected = 1.0;
		let actual = normaliser.normalise(input);
		assert_eq!(expected, actual);
	}

	#[test]
	fn test_normalise_with_no_bounds() {
		let normaliser = Clipping {
			min: None,
			max: None,
		};
		let input = 0.5;
		let expected = 0.5;
		let actual = normaliser.normalise(input);
		assert_eq!(expected, actual);
	}
}