use crate::model::TVec;
use num_traits::One;
pub fn multi_broadcast<T>(shapes: &[impl AsRef<[T]>]) -> Option<TVec<T>>
where
T: One + PartialEq + Copy,
{
let len = shapes.iter().map(|shape| shape.as_ref().len()).max()?;
let mut shape = tvec!();
for i in 0..len {
let mut wanted_size = T::one();
for shape in shapes {
let len = shape.as_ref().len();
let dim = if i < len {
shape.as_ref()[len - i - 1]
} else {
T::one()
};
if dim != T::one() {
if wanted_size != T::one() && dim != wanted_size {
return None;
}
wanted_size = dim;
}
}
shape.push(wanted_size)
}
shape.reverse();
Some(shape)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn onnx_1() {
assert_eq!(
multi_broadcast(&tvec![tvec![2, 3, 4, 5], tvec![]]),
Some(tvec![2, 3, 4, 5])
)
}
#[test]
fn onnx_2() {
assert_eq!(
multi_broadcast(&tvec![tvec![2, 3, 4, 5], tvec![5]]),
Some(tvec![2, 3, 4, 5])
)
}
#[test]
fn onnx_3() {
assert_eq!(
multi_broadcast(&tvec![tvec![4, 5], tvec![2, 3, 4, 5]]),
Some(tvec![2, 3, 4, 5])
)
}
#[test]
fn onnx_4() {
assert_eq!(
multi_broadcast(&tvec![tvec![1, 4, 5], tvec![2, 3, 4, 1]]),
Some(tvec![2, 3, 4, 5])
)
}
#[test]
fn onnx_5() {
assert_eq!(
multi_broadcast(&tvec![tvec![3, 4, 5], tvec![2, 1, 1, 1]]),
Some(tvec![2, 3, 4, 5])
)
}
}