X-Git-Url: http://gitweb.hachti.de/?a=blobdiff_plain;f=sw%2Ff4%2FFRTSRC%2Ftan.ra;fp=sw%2Ff4%2FFRTSRC%2Ftan.ra;h=89193f3a9ab9e9d6547b5635fb542e3e98be0f43;hb=7af5ad59491ddf2066641aef1e0025a337c0f247;hp=0000000000000000000000000000000000000000;hpb=919757fd611e482003ce51f366f6783cab73dea3;p=pdp8.git

diff --git a/sw/f4/FRTSRC/tan.ra b/sw/f4/FRTSRC/tan.ra
new file mode 100644
index 0000000..89193f3
--- /dev/null
+++ b/sw/f4/FRTSRC/tan.ra
@@ -0,0 +1,56 @@
+/
+/
+/	T  A  N
+/	-  -  -
+/
+/SUBROUTINE 	TAN(X)
+/
+/ VERSION 5A 4-27-77  PT
+/
+	SECT	TAN
+	JA	#TAN
+	EXTERN	#ARGER
+TANER,	TRAP4	#ARGER
+	TEXT	+TAN   +
+TANXR,	SETX	XRTAN
+	SETB	BPTAN
+BPTAN,	FNOP
+	0
+	0
+XRTAN,	F 0.0
+TAN1,	F 0.0
+TAN2,	F 0.0
+	ORG	10*3+BPTAN
+	FNOP
+	JA	TANXR
+	0
+TANRTN,	JA	.
+	BASE	0
+#TAN,	STARTD
+	FLDA	10*3
+	FSTA	TANRTN
+	FLDA	0
+	SETX	XRTAN
+	SETB	BPTAN
+	BASE	BPTAN
+	LDX	1,1
+	FSTA	BPTAN
+	FLDA%	BPTAN,1	/ADDR OF X
+	FSTA	BPTAN
+	STARTF
+	FLDA%	BPTAN	/GET X
+	JEQ	TANRTN	/IF 0 RTN NOW
+	FSTA	TAN1	/SAVE FOR A SECOND
+	EXTERN	COS
+	JSR	COS	/TAKE COS(X)
+	JA	.+4
+	JA	TAN1
+	JEQ	TANER	/COS=0. A NO-NO
+	FSTA	TAN2	/SAV IT
+	EXTERN	SIN
+	JSR	SIN	/NOW TAKE SIN(X)
+	JA	.+4
+	JA	TAN1
+	FDIV	TAN2	/DIV BY COS(X)
+	JA	TANRTN
+