Function ndarray_einsum_beta::slow_versions::slow_einsum

pub fn slow_einsum<A: LinalgScalar>(
    input_string: &str, 
    operands: &[&dyn ArrayLike<A>]
) -> Result<ArrayD<A>, &'static str>

Very inefficient and explicit to be removed or only used for testing

Iterates through all possible combinations of index values and executes thousands of times slower than real implementation.