conspire 0.7.7

The Rust interface to conspire.
Documentation
#[cfg(test)]
mod test;

use crate::{
    constitutive::{
        ConstitutiveError,
        solid::{Solid, TWO_THIRDS, elastic::Elastic},
    },
    math::{ContractThirdFourthWithFirstSecond, IDENTITY_00, Quantity, Rank2, TensorRank4},
    mechanics::{
        Deformation, DeformationGradient, SecondPiolaKirchhoffStress,
        SecondPiolaKirchhoffTangentStiffness,
    },
    units::Stress,
};

#[doc = include_str!("doc.md")]
#[derive(Clone, Debug)]
pub struct Hencky {
    /// The bulk modulus $`\kappa`$.
    pub bulk_modulus: Quantity<Stress>,
    /// The shear modulus $`\mu`$.
    pub shear_modulus: Quantity<Stress>,
}

impl Solid for Hencky {
    fn bulk_modulus(&self) -> Quantity<Stress> {
        self.bulk_modulus
    }
    fn shear_modulus(&self) -> Quantity<Stress> {
        self.shear_modulus
    }
}

impl Elastic for Hencky {
    #[doc = include_str!("second_piola_kirchhoff_stress.md")]
    fn second_piola_kirchhoff_stress(
        &self,
        deformation_gradient: &DeformationGradient,
    ) -> Result<SecondPiolaKirchhoffStress, ConstitutiveError> {
        let _jacobian = self.jacobian(deformation_gradient)?;
        let (deviatoric_strain, strain_trace) = (deformation_gradient
            .right_cauchy_green()
            .logm()
            .map_err(|error| ConstitutiveError::upstream(error, self))?
            * 0.5)
            .deviatoric_and_trace();
        Ok(deviatoric_strain * (2.0 * self.shear_modulus())
            + IDENTITY_00 * (self.bulk_modulus() * strain_trace))
    }
    #[doc = include_str!("second_piola_kirchhoff_tangent_stiffness.md")]
    fn second_piola_kirchhoff_tangent_stiffness(
        &self,
        deformation_gradient: &DeformationGradient,
    ) -> Result<SecondPiolaKirchhoffTangentStiffness, ConstitutiveError> {
        let _jacobian = self.jacobian(deformation_gradient)?;
        let right_cauchy_green = deformation_gradient.right_cauchy_green();
        let deformation_gradient_transpose = deformation_gradient.transpose();
        let scaled_deformation_gradient_transpose =
            &deformation_gradient_transpose * self.shear_modulus();
        Ok((right_cauchy_green
            .dlogm()
            .map_err(|error| ConstitutiveError::upstream(error, self))?
            .contract_third_fourth_with_first_second(
                &(TensorRank4::dyad_il_jk(&IDENTITY_00, &scaled_deformation_gradient_transpose)
                    + TensorRank4::dyad_ik_jl(
                        &scaled_deformation_gradient_transpose,
                        &IDENTITY_00,
                    )),
            ))
            + (TensorRank4::dyad_ij_kl(
                &(IDENTITY_00 * (self.bulk_modulus() - TWO_THIRDS * self.shear_modulus())),
                &deformation_gradient_transpose.inverse(),
            )))
    }
}