Penstemon digitalis Penstemon digitalis Penstemon digitalis (foxglove beard-tongue, foxglove beardtongue, or talus slope penstemon) is a plant in the plantain family, Plantaginaceae. The flowers are white and are borne in summer. It is native to eastern Canada and eastern and southeastern United States. "Penstemon digitalis" is a glabrous 3 to 5 foot tall herbaceous plant with opposite, shiny green, simple leaves, on slender, purple stems. The leaves are up to 5 inches long. While upright, the stems average anywhere from 2 to 3 feet tall. The flowering panicle extends to almost one third of the plant's height and has pairs of branches
Derive (computer algebra system) Derive (computer algebra system) Derive was a computer algebra system, developed as a successor to muMATH by the Soft Warehouse in Honolulu, Hawaii, now owned by Texas Instruments. Derive was implemented in , also by Soft Warehouse. The first release was in 1988 for DOS. It was discontinued on June 29, 2007 in favor of the TI-Nspire CAS. The last and final version is Derive 6.1 for Windows. Since Derive required comparably little memory, it was suitable for use on older and smaller machines. It was available for the DOS and Windows platforms and was used also in TI pocket