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2.1.3.3 Denormalized Floats

CMU Common Lisp supports IEEE denormalized floats. Denormalized floats provide a mechanism for gradual underflow. The Common Lisp  float-precision function returns the actual precision of a denormalized float, which will be less than  float-digits. Note that in order to generate (or even print) denormalized floats, trapping must be disabled for the underflow exception (see section 2.1.3.4.) The Common Lisp least-positive-format-float constants are denormalized.

[Function]
extensions:float-normalized-p x

This function returns true if x is a denormalized float. x must be a float.



Raymond Toy
Mon Jul 14 09:11:27 EDT 1997