I am guessing that the following has something to do with precision of large numbers in j805 and is also true for j806.
(; datatype) 999999999999999.3 ┌────┬────────┐ │1e15│floating│ └────┴────────┘ (; datatype) 9999999999999999.3 ┌─────────────────┬───────┐ │10000000000000000│integer│ └─────────────────┴───────┘ (; datatype) 99999999999999999.3 ┌──────────────────┬───────┐ │100000000000000000│integer│ └──────────────────┴───────┘ (; datatype) 999999999999999999.3 ┌───────────────────┬───────┐ │1000000000000000000│integer│ └───────────────────┴───────┘ (; datatype) 9999999999999999999.3 ┌────┬────────┐ │1e19│floating│ └────┴────────┘ JVERSION Engine: j805/j64/darwin Release: commercial/2016-12-11T08:17:56 Library: 8.05.14 Qt IDE: 1.5.4/5.6.2 Platform: Darwin 64 Installer: J805 install InstallPath: /applications/j64-805 Contact: www.jsoftware.com Further investigation shows me it was not this way with the 32 bit version of j701, so it may be an artifact of moving to 64 bit? (; datatype) 999999999999999.3 ┌────┬────────┐ │1e15│floating│ └────┴────────┘ (; datatype) 9999999999999999.3 ┌────┬────────┐ │1e16│floating│ └────┴────────┘ (; datatype) 999999999999999999.3 ┌────┬────────┐ │1e18│floating│ └────┴────────┘ (; datatype) 9999999999999999999.3 ┌────┬────────┐ │1e19│floating│ └────┴────────┘ JVERSION Engine: j701/2011-01-10/11:25 Library: 7.01.088 Platform: Darwin 32 Installer: j701a_mac_intel.dmg InstallPath: /Applications/j701 Cheers, bob ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm