sorting out...

[ieee754fpu.git] / src / add / fsqrt.py

diff --git a/src/add/fsqrt.py b/src/add/fsqrt.py
index d94700ff50589b9629369d891c81bec02b694515..e9b856ed459bd999023809fcdbc4f58dcea5080b 100644 (file)
--- a/src/add/fsqrt.py
+++ b/src/add/fsqrt.py
@@ -1,3 +1,6 @@
+from sfpy import Float32
+
+
 # XXX DO NOT USE, fails on num=65536.  wark-wark...
 def sqrtsimple(num):
     res = 0
@@ -25,20 +28,20 @@ def sqrt(num):
     for i in range(15, -1, -1): # negative ranges are weird...
 
         if (R>=0):
-        
+
             R = (R<<2)|((D>>(i+i))&3)
             R = R-((Q<<2)|1) #/*-Q01*/
-         
+
         else:
 
             R = (R<<2)|((D>>(i+i))&3)
             R = R+((Q<<2)|3) #/*+Q11*/
-        
+
         if (R>=0):
             Q = (Q<<1)|1 #/*new Q:*/
         else:
             Q = (Q<<1)|0 #/*new Q:*/
-    
+
 
     if (R<0):
         R = R+((Q<<1)|1)
@@ -96,7 +99,26 @@ if __name__ == '__main__':
             ms, es = main(m, e)
             print("m:%d e:%d sqrt: m:%d e:%d" % (m, e, ms, es))
 
+    x = Float32(1234.123456789)
+    xbits = x.bits
+
+    print (x, type(x))
+    print (xbits, type(xbits))
+    s, e, m = decode_fp32(xbits)
+    print(s, e, m, hex(m))
+
+    se, sm = main(e, m)
+    print("our sqrt", se, sm, hex(sm))
+
+    sq_test = x.sqrt()
+    sq_xbits = sq_test.bits
+    s, e, m = decode_fp32(sq_xbits)
+    print ("sf16 sqrt", s, e, m, hex(m))
 """
+
+Notes:
+https://pdfs.semanticscholar.org/5060/4e9aff0e37089c4ab9a376c3f35761ffe28b.pdf
+
 //This is the main code of integer sqrt function found here:http://verilogcodes.blogspot.com/2017/11/a-verilog-function-for-finding-square-root.html
 //