Convexity and positivity of bivariate quadratic Bézier surfaces over a rectangle
Autor: | You-dong Ding |
---|---|
Rok vydání: | 2001 |
Předmět: | |
Zdroj: | Journal of Shanghai University (English Edition). 5:20-28 |
ISSN: | 1863-236X 1007-6417 |
Popis: | With the help of several discriminants about the zero points of a quartic polynomial, the sufficient and necessary conditions for the positivity and nonnegativity of the quartic polynomial over an interval I⊂(−∞, +∞) was derived. Based on these conclusions, the sufficient and necessary conditions for the positivity and convexity of the 2×2 Bezier surface over a rectangle were obtained. A simple sufficient condition was deduced also and finally several examples were given. |
Databáze: | OpenAIRE |
Externí odkaz: |