
QEPCAD is an implementation of quantifier elimination by partial cylindrical algebraic decomposition due originally to Hoon Hong, and subsequently added on to by many others. It is an interactive command-line program written in C/C++, and based on the SACLIB library. Presented here is QEPCAD B version 1.x, the "B" designating a substantial departure from the original QEPCAD and distinguishing it from any development of the original that may proceed in a different direction. QEPCAD and the SACLIB library are the result of a program of research by George Collins and his PhD students that has spanned several decades ... and continues still!