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README.md

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 # matADi
 Material Definition with Automatic Differentiation (AD)
 
+![matADi](https://raw.githubusercontent.com/adtzlr/matadi/main/docs/logo/matadi-logo.svg)
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 matADi is a simple Python module which acts as a wrapper on top of [casADi](https://web.casadi.org/) [[1](https://doi.org/10.1007/s12532-018-0139-4)] for easy definitions of hyperelastic strain energy functions. [Gradients](https://en.wikipedia.org/wiki/Gradient) (stresses) and [hessians](https://en.wikipedia.org/wiki/Hessian_matrix) (elasticity tensors) are carried out by casADi's powerful and fast [**Automatic Differentiation (AD)**](https://en.wikipedia.org/wiki/Automatic_differentiation) capabilities. It is designed to handle inputs with trailing axes which is especially useful for the application in Python-based finite element modules like [scikit-fem](https://scikit-fem.readthedocs.io/en/latest/) or [FElupe](https://adtzlr.github.io/felupe/). Mixed-field formulations are supported as well as single-field formulations.