LimitedPrecisionReal.st
changeset 7405 9b0334a4591b
parent 7403 857702a5a921
child 7418 521174de046d
--- a/LimitedPrecisionReal.st	Tue Jun 17 16:12:12 2003 +0200
+++ b/LimitedPrecisionReal.st	Tue Jun 17 16:35:41 2003 +0200
@@ -37,12 +37,29 @@
 
 documentation
 "
-    Abstract superclass for single and double (and maybe more) 
-    precision real numbers (i.e. Float and Double).
+    Abstract superclass for any-precision floating point numbers (i.e. Float and Double).
 
     Due to historic reasons, ST/X's Floats are what Doubles are in ST-80.
     This may change soon (implementing LPReal is a first step towards this).
 
+    Range and Precision of Storage Formats:
+
+      Format |     Class  | Significant Digits (Binary) | Smallest Pos Number | Largest Pos Number | Significant Digits (Decimal)
+      -------+------------+-----------------------------+---------------------+--------------------+------------------------------    
+      single | ShortFloat |         24                  |  1.175... 10-38     |  3.402... 10+38    |      6-9
+      -------+------------+-----------------------------+---------------------+--------------------+------------------------------    
+      double | Float      |         53                  |  2.225... 10-308    |  1.797... 10+308   |     15-17
+      -------+------------+-----------------------------+---------------------+--------------------+------------------------------    
+      double | LongFloat  |        113                  |  3.362... 10-4932   |  1.189... 10+4932  |     33-36
+      ext    |            |                             |                     |                    |
+      (SPARC)|            |                             |                     |                    |
+      -------+            |-----------------------------+---------------------+--------------------+------------------------------    
+      double |            |         64                  |  3.362... 10-4932   |  1.189... 10+4932  |     18-21
+      ext    |            |                             |                     |                    |
+      (x86)  |            |                             |                     |                    |
+      -------+------------+-----------------------------+---------------------+--------------------+------------------------------    
+
+
     [author:]
         Claus Gittinger
 
@@ -936,7 +953,7 @@
 !LimitedPrecisionReal class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/LimitedPrecisionReal.st,v 1.53 2003-06-17 14:10:40 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/LimitedPrecisionReal.st,v 1.54 2003-06-17 14:35:32 cg Exp $'
 ! !
 
 LimitedPrecisionReal initialize!