“…Anomalous sub diffusion wherein the spread of particles occurs slower than the classical diffusion was numerically solved via compact finite differences in space and Grn¨wald–Letnikov scheme in fractional time in Al-Shibani et al (2013). A few more such recent attempts are variational iteration method (Ates and Yıldırım, 2010), operational Tau method (Vanani and Aminataei, 2012), homotopy perturbation method (Liu and Dong, 2015), reproducing kernel (Arqub, 2018), H2 matrix representation (Boukaram et al , 2020), nonpolynomial spline functions (Hasan and Salim, 2021), Legendre spectral method (Liu and Lu, 2021), Sinc and B-Spline interpolation (Adibmanesha and Rashidiniab, 2021), Chebyshev wavelets (Dincel and Polat, 2021), meshless methods (Nikan et al , 2021; Bavi et al , 2022), Crank–Nicholson method (Xie and Fang, 2022), neural network method with shifted Legendre orthogonal polynomials (Qu et al , 2022), compact implicit difference method (Ali et al , 2022), finite volume method (Fang et al , 2022) and boundary integral equation method (Yao and Wang, 2022).…”