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-rw-r--r--test/math/elog.c92
1 files changed, 0 insertions, 92 deletions
diff --git a/test/math/elog.c b/test/math/elog.c
deleted file mode 100644
index bc517b197..000000000
--- a/test/math/elog.c
+++ /dev/null
@@ -1,92 +0,0 @@
-/* xlog.c */
-/* natural logarithm */
-/* by Stephen L. Moshier. */
-
-#include "mconf.h"
-#include "ehead.h"
-
-
-
-void elog( x, y )
-unsigned short *x, *y;
-{
-unsigned short xx[NE], z[NE], a[NE], b[NE], t[NE], qj[NE];
-long ex;
-int fex;
-
-
-if( x[NE-1] & (unsigned short )0x8000 )
- {
- eclear(y);
- mtherr( "elog", DOMAIN );
- return;
- }
-if( ecmp( x, ezero ) == 0 )
- {
- einfin( y );
- eneg(y);
- mtherr( "elog", SING );
- return;
- }
-if( ecmp( x, eone ) == 0 )
- {
- eclear( y );
- return;
- }
-
-/* range reduction: log x = log( 2**ex * m ) = ex * log2 + log m */
-efrexp( x, &fex, xx );
-/*
-emov(x, xx );
-ex = xx[NX-1] & 0x7fff;
-ex -= 0x3ffe;
-xx[NX-1] = 0x3ffe;
-*/
-
-/* Adjust range to 1/sqrt(2), sqrt(2) */
-esqrt2[NE-1] -= 1;
-if( ecmp( xx, esqrt2 ) < 0 )
- {
- fex -= 1;
- emul( xx, etwo, xx );
- }
-esqrt2[NE-1] += 1;
-
-esub( eone, xx, a );
-if( a[NE-1] == 0 )
- {
- eclear( y );
- goto logdon;
- }
-eadd( eone, xx, b );
-ediv( b, a, y ); /* store (x-1)/(x+1) in y */
-
-emul( y, y, z );
-
-emov( eone, a );
-emov( eone, b );
-emov( eone, qj );
-do
- {
- eadd( etwo, qj, qj ); /* 2 * i + 1 */
- emul( z, a, a );
- ediv( qj, a, t );
- eadd( t, b, b );
- }
-while( ((b[NE-1] & 0x7fff) - (t[NE-1] & 0x7fff)) < NBITS );
-
-
-emul( b, y, y );
-emul( y, etwo, y );
-
-logdon:
-
-/* now add log of 2**ex */
-if( fex != 0 )
- {
- ex = fex;
- ltoe( &ex, b );
- emul( elog2, b, b );
- eadd( b, y, y );
- }
-}