Mercurial > sdl-ios-xcode
view src/video/Xext/extensions/xf86dga1str.h @ 2752:edd2839b36f7
http://sources.redhat.com/ml/newlib/2002/msg00230.html
Stephen L Moshier wrote:
>
> pow(x,y) returns 0 when x is very close to -1.0 and y is very large.
> The following test program prints
>
> pow(1.0000000000000002e+00 4.5035996273704970e+15) = 2.7182818284590455e+00
> pow(-1.0000000000000002e+00 4.5035996273704970e+15) =0.0000000000000000e+00
> pow(9.9999999999999978e-01 4.5035996273704970e+15) = 3.6787944117144222e-01
> pow(-9.9999999999999978e-01 4.5035996273704970e+15) = 0.0000000000000000e+00
>
> which is incorrect for the negative arguments raised to an odd integer
> power.
>
> -----
> double pow (double, double);
>
> int
> main ()
> {
> double x, y, z;
>
> x = 1.0 + pow (2.0, -52.0);
> y = 1.0 + pow (2.0, 52.0);
> z = pow (x, y);
> printf ("pow(%.16e %.16e) = %.16e\n", x, y, z);
> x = -x;
> z = pow (x, y);
> printf ("pow(%.16e %.16e) = %.16e\n", x, y, z);
> x = 1.0 - pow (2.0, -52.0);
> z = pow (x, y);
> printf ("pow(%.16e %.16e) = %.16e\n", x, y, z);
> x = -x;
> z = pow (x, y);
> printf ("pow(%.16e %.16e) = %.16e\n", x, y, z);
> }
> -----
>
> Here is a patch for newlib/libm/math/epow.c:
Patch checked in and duplicated for ef_pow.c. Thanks.
-- Jeff J.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 15 Sep 2008 04:31:30 +0000 |
parents | c121d94672cb |
children |
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/* $XFree86: xc/include/extensions/xf86dga1str.h,v 1.2 1999/05/03 12:15:37 dawes Exp $ */ /* Copyright (c) 1995 Jon Tombs Copyright (c) 1995 XFree86 Inc. */ #ifndef _XF86DGASTR1_H_ #define _XF86DGASTR1_H_ typedef struct _XF86DGAQueryVersion { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; } xXF86DGAQueryVersionReq; #define sz_xXF86DGAQueryVersionReq 4 typedef struct { BYTE type; /* X_Reply */ BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD16 majorVersion B16; /* major version of DGA protocol */ CARD16 minorVersion B16; /* minor version of DGA protocol */ CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; CARD32 pad6 B32; } xXF86DGAQueryVersionReply; #define sz_xXF86DGAQueryVersionReply 32 typedef struct _XF86DGAGetVideoLL { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetVideoLL */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetVideoLLReq; #define sz_xXF86DGAGetVideoLLReq 8 typedef struct _XF86DGAInstallColormap { CARD8 reqType; CARD8 dgaReqType; CARD16 length B16; CARD16 screen B16; CARD16 pad2; CARD32 id B32; /* colormap. */ } xXF86DGAInstallColormapReq; #define sz_xXF86DGAInstallColormapReq 12 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 offset B32; CARD32 width B32; CARD32 bank_size B32; CARD32 ram_size B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetVideoLLReply; #define sz_xXF86DGAGetVideoLLReply 32 typedef struct _XF86DGADirectVideo { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGADirectVideo */ CARD16 length B16; CARD16 screen B16; CARD16 enable B16; } xXF86DGADirectVideoReq; #define sz_xXF86DGADirectVideoReq 8 typedef struct _XF86DGAGetViewPortSize { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetViewPort */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetViewPortSizeReq; #define sz_xXF86DGAGetViewPortSizeReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 width B32; CARD32 height B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetViewPortSizeReply; #define sz_xXF86DGAGetViewPortSizeReply 32 typedef struct _XF86DGASetViewPort { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGASetViewPort */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; CARD32 x B32; CARD32 y B32; } xXF86DGASetViewPortReq; #define sz_xXF86DGASetViewPortReq 16 typedef struct _XF86DGAGetVidPage { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGAGetVidPage */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAGetVidPageReq; #define sz_xXF86DGAGetVidPageReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 vpage B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAGetVidPageReply; #define sz_xXF86DGAGetVidPageReply 32 typedef struct _XF86DGASetVidPage { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_XF86DGASetVidPage */ CARD16 length B16; CARD16 screen B16; CARD16 vpage B16; } xXF86DGASetVidPageReq; #define sz_xXF86DGASetVidPageReq 8 typedef struct _XF86DGAQueryDirectVideo { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; CARD16 screen B16; CARD16 pad B16; } xXF86DGAQueryDirectVideoReq; #define sz_xXF86DGAQueryDirectVideoReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 flags B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAQueryDirectVideoReply; #define sz_xXF86DGAQueryDirectVideoReply 32 typedef struct _XF86DGAViewPortChanged { CARD8 reqType; /* always DGAReqCode */ CARD8 dgaReqType; /* always X_DGAQueryVersion */ CARD16 length B16; CARD16 screen B16; CARD16 n B16; } xXF86DGAViewPortChangedReq; #define sz_xXF86DGAViewPortChangedReq 8 typedef struct { BYTE type; BOOL pad1; CARD16 sequenceNumber B16; CARD32 length B32; CARD32 result B32; CARD32 pad B32; CARD32 pad2 B32; CARD32 pad3 B32; CARD32 pad4 B32; CARD32 pad5 B32; } xXF86DGAViewPortChangedReply; #define sz_xXF86DGAViewPortChangedReply 32 #endif /* _XF86DGASTR1_H_ */ /* vi: set ts=4 sw=4 expandtab: */