# “data analysis”

### Fast spin $\pm 2$ spherical harmonics transforms and application in cosmology

Abstract: A fast and exact algorithm is developed for the spin $$\pm2$$ spherical harmonics transforms on equi-angular pixelizations on the sphere. It is based on the Driscoll and Healy fast scalar spherical harmonics transform.

### Fast directional correlation on the sphere with steerable filters

Abstract: A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through simple quadrature is of order $$O(L^5)$$, where $$2L$$ stands for the square-root of the number of sampling points on the sphere, also setting a band limit L for the signals and filters considered.