Detroit's Marwil Bookstore or purchasing them on the internet from online competitors, such as Amazon and eBay. After Marwil had been in business at WSU for some 59 years, Brian Kramer had seen textbook prices nearly triple over a period of two decades. According to a 2005 survey conducted by the National Association of College Students, about 25 percent of students had begun purchasing textbooks online. Another drastic change was when Wayne State opened a $6 million, 28,000-square-foot Barnes & Noble college bookstore right across the street in 2002. Marwil didn't have the fancy store front, cafe or music and apparel that was
Cadabra (computer program) Cadabra (computer program) Cadabra is a computer algebra system designed specifically for the solution of problems encountered in quantum field theory and string theory. The first version of Cadabra has been developped around 2001 to for computing higher-derivative string theory correction to supergravity. Released under the GNU General Public License, Cadabra is free software. Cadabra has extensive functionality for tensor polynomial simplification including multi-term symmetries, fermions and anti-commuting variables, Clifford algebras and Fierz transformations, implicit coordinate dependence, multiple index types and many more. The input format is a subset of TeX. Both a command-line and a graphical interface are available.