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diff --git a/libm/man/atan2.3 b/libm/man/atan2.3 deleted file mode 100644 index 421e17d..0000000 --- a/libm/man/atan2.3 +++ /dev/null @@ -1,187 +0,0 @@ -.\" Copyright (c) 1991 The Regents of the University of California. -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 3. All advertising materials mentioning features or use of this software -.\" must display the following acknowledgement: -.\" This product includes software developed by the University of -.\" California, Berkeley and its contributors. -.\" 4. Neither the name of the University nor the names of its contributors -.\" may be used to endorse or promote products derived from this software -.\" without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND -.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE -.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE -.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL -.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS -.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) -.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT -.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY -.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF -.\" SUCH DAMAGE. -.\" -.\" from: @(#)atan2.3 5.1 (Berkeley) 5/2/91 -.\" $FreeBSD: src/lib/msun/man/atan2.3,v 1.14 2005/01/28 21:13:34 ru Exp $ -.\" -.Dd January 14, 2005 -.Dt ATAN2 3 -.Os -.Sh NAME -.Nm atan2 , -.Nm atan2f -.Nd arc tangent functions of two variables -.Sh LIBRARY -.Lb libm -.Sh SYNOPSIS -.In math.h -.Ft double -.Fn atan2 "double y" "double x" -.Ft float -.Fn atan2f "float y" "float x" -.Sh DESCRIPTION -The -.Fn atan2 -and the -.Fn atan2f -functions compute the principal value of the arc tangent of -.Fa y/ Ns Ar x , -using the signs of both arguments to determine the quadrant of -the return value. -.Sh RETURN VALUES -The -.Fn atan2 -and the -.Fn atan2f -functions, if successful, -return the arc tangent of -.Fa y/ Ns Ar x -in the range -.Bk -words -.Bq \&- Ns \*(Pi , \&+ Ns \*(Pi -.Ek -radians. -Here are some of the special cases: -.Bl -column atan_(y,x)_:=____ sign(y)_(Pi_atan2(Xy_xX))___ -.It Fn atan2 y x No := Ta -.Fn atan y/x Ta -if -.Ar x -> 0, -.It Ta sign( Ns Ar y Ns )*(\*(Pi - -.Fn atan "\\*(Bay/x\\*(Ba" ) Ta -if -.Ar x -< 0, -.It Ta -.No 0 Ta -if x = y = 0, or -.It Ta -.Pf sign( Ar y Ns )*\\*(Pi/2 Ta -if -.Ar x -= 0 \(!= -.Ar y . -.El -.Sh NOTES -The function -.Fn atan2 -defines "if x > 0," -.Fn atan2 0 0 -= 0 despite that previously -.Fn atan2 0 0 -may have generated an error message. -The reasons for assigning a value to -.Fn atan2 0 0 -are these: -.Bl -enum -offset indent -.It -Programs that test arguments to avoid computing -.Fn atan2 0 0 -must be indifferent to its value. -Programs that require it to be invalid are vulnerable -to diverse reactions to that invalidity on diverse computer systems. -.It -The -.Fn atan2 -function is used mostly to convert from rectangular (x,y) -to polar -.if n\ -(r,theta) -.if t\ -(r,\(*h) -coordinates that must satisfy x = -.if n\ -r\(**cos theta -.if t\ -r\(**cos\(*h -and y = -.if n\ -r\(**sin theta. -.if t\ -r\(**sin\(*h. -These equations are satisfied when (x=0,y=0) -is mapped to -.if n \ -(r=0,theta=0). -.if t \ -(r=0,\(*h=0). -In general, conversions to polar coordinates -should be computed thus: -.Bd -unfilled -offset indent -.if n \{\ -r := hypot(x,y); ... := sqrt(x\(**x+y\(**y) -theta := atan2(y,x). -.\} -.if t \{\ -r := hypot(x,y); ... := \(sr(x\u\s82\s10\d+y\u\s82\s10\d) -\(*h := atan2(y,x). -.\} -.Ed -.It -The foregoing formulas need not be altered to cope in a -reasonable way with signed zeros and infinities -on a machine that conforms to -.Tn IEEE 754 ; -the versions of -.Xr hypot 3 -and -.Fn atan2 -provided for -such a machine are designed to handle all cases. -That is why -.Fn atan2 \(+-0 \-0 -= \(+-\*(Pi -for instance. -In general the formulas above are equivalent to these: -.Bd -unfilled -offset indent -.if n \ -r := sqrt(x\(**x+y\(**y); if r = 0 then x := copysign(1,x); -.if t \ -r := \(sr(x\(**x+y\(**y);\0\0if r = 0 then x := copysign(1,x); -.Ed -.El -.Sh SEE ALSO -.Xr acos 3 , -.Xr asin 3 , -.Xr atan 3 , -.Xr cos 3 , -.Xr cosh 3 , -.Xr math 3 , -.Xr sin 3 , -.Xr sinh 3 , -.Xr tan 3 , -.Xr tanh 3 -.Sh STANDARDS -The -.Fn atan2 -function conforms to -.St -isoC . |