v 4.2.8

14/09/2007 Joe Chuma

The Heaviside function has been added.
HEAVISIDE(x) = 0.0 for x < 0, 0.5 for x = 0, 1.0 for x > 0

(linux only) The dependency on libxml2 has been removed. Extrema now uses wxXmlDocument and wxXmlNode instead.

(linux only) Modified Command, FCN_adev, FCN_mean, FCN_gmean, FCN_rms, FCN_skew, FCN_stdev, FCN_date, FCN_time, CMD_get, CMD_read, CMD_scalar, CMD_set, GRA_axis, ExSpinCtrlD, ExSpinCtrlI, and ExColorCtrl to comply with the gcc v4.1.x compiler.