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QD (Library)


QD is a package that supports both a double-double datatype with about 32 decimal digits,
and a quad-double datatype with about 64 decimal digits.

The library is written by David H. Bailey et. al from the Lawrence Berkeley National Laboratory (see

In addition to the basic arithmetic operations (add, subtract, multiply, divide, square root), common transcendental functions such as the exponential, logarithm, trigonometric and hyperbolic functions are also included.

Availability Table

System Versions
wobbie 2.3.13, 2.3.17
vdi-centos6 2.3.13, 2.3.17
iqaluk 2.3.13, 2.3.17

Change Log

o Oct 1, 2015: Installed qd/intel1503/2.3.17 on angel, brown, copper, goblin, iqaluk, kraken, monk, mosaic, orca, redfin, saw, tembo, windeee and wobbie. Installed qd/intel/2.3.13 on vdi-centos6, copper and mosaic.
Jan 9, 2014: Installed qd/2.3.13 on wobbie.
Jun 3, 2013: Removed qd/2.3.8 from angel, goblin, hound, kraken, requin, saw and tope
Apr 22, 2013: Installed qd/2.3.13 on angel, brown, goblin, hound, iqaluk, monk, orca, redfin and saw.