  We have obtained accurate dust reddening from far-ultraviolet (UV) to the
mid-infrared (IR) for up to 5 million stars by the star-pair algorithm based on
LAMOST stellar parameters along with GALEX, Pan-STARRS 1, Gaia, SDSS, 2MASS,
and WISE photometric data. The typical errors are between 0.01-0.03 mag for
most colors. We derived the empirical reddening coefficients for 21 colors both
in the traditional (single valued) way and as a function of Teff and E(B-V) by
using the largest samples of accurate reddening measurements, together with the
extinction values from Schlegel et al. The corresponding extinction
coefficients have also been obtained. The results are compared with model
predictions and generally in good agreement. Comparisons with measurements in
the literature show that the Teff- and E(B-V)-dependent coefficients explain
the discrepancies between different measurements naturally, i.e., using sample
stars of different temperatures and reddening. Our coefficients are mostly
valid in the extinction range of 0-0.5 mag and the temperature range of
4000-10000 K. We recommend that the new Teff and E(B-V) dependent reddening and
extinction coefficients should be used in the future. A Python package is also
provided for the usage of the coefficient
