blat: inc/slog.h Source File

00001 /* slog - fixed point scaled logarithm stuff. */
00002 #ifndef SLOG_H
00003 #define SLOG_H
00004 
00005 extern double fSlogScale;       /* Convert to fixed point by multiplying by this. */
00006 extern double invSlogScale;     /* To convert back to floating point use this. */
00007 
00008 int slog(double val);
00009 /* Return scaled log. */
00010 
00011 int carefulSlog(double val);
00012 /* Returns scaled log that makes sure there's no int overflow. */
00013 
00014 double invSlog(int scaledLog);
00015 /* Inverse of slog. */
00016 
00017 #endif /* SLOG_H */
00018