33 lines
408 B
C
33 lines
408 B
C
/* $Header$ */
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/*
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computes a^b.
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uses log and exp
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*/
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double _log(), _exp();
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double
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_power(base,pownr)
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double pownr, base;
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{
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double temp;
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long l;
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if(pownr <= 0.0) {
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if(pownr == 0.0) {
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if(base <= 0.0)
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error(3);
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return(0.0);
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}
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l = base;
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if(l != base)
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error(3);
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temp = _exp(base * _log(-pownr));
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if(l & 1)
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temp = -temp;
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return(temp);
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}
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return(_exp(base * _log(pownr)));
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}
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