Paul Lipscomb
22 lines
522 B
C
22 lines
522 B
C
#ifndef _WDL_DB2VAL_H_
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#define _WDL_DB2VAL_H_
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#include <math.h>
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#define TWENTY_OVER_LN10 8.6858896380650365530225783783321
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#define LN10_OVER_TWENTY 0.11512925464970228420089957273422
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#define DB2VAL(x) exp((x)*LN10_OVER_TWENTY)
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static inline double VAL2DB(double x)
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{
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if (x < 0.0000000298023223876953125) return -150.0;
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double v=log(x)*TWENTY_OVER_LN10;
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return v<-150.0?-150.0:v;
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}
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static inline double VAL2DB_EX(double x, double mindb)
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{
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return x <= DB2VAL(mindb) ? mindb : (log(x)*TWENTY_OVER_LN10);
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}
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#endif |