83 lines
1.5 KiB
C
83 lines
1.5 KiB
C
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/* DEC *NetPresentValue(net, flows, nflow, intr)
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*
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* ARGUMENT
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* DEC *net, **flows, *intr;
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* int nflow;
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*
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* DESCRIPTION
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* Calculates the net present value of a series of cash flows.
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* The nflow cash flows in the array flows are processed at interest
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* rate intr. The net present value, rounded to two decimal places,
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* is stored in net.
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*
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* SIDE EFFECTS
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* None.
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*
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* RETURNS
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* net if successful, otherwise GM_NULL.
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*
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* POSSIBLE ERRORS
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* GM_NULLPOINTER
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* GM_ARGVAL
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*
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* AUTHOR
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* Jared Levy
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* Copyright (C) 1988-1990 Greenleaf Software Inc. All rights reserved.
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*
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* MODIFICATIONS
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*
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*
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*/
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#include <stdio.h>
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#include "gm.h"
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#include "gmsystem.h"
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DEC *NetPresentValue(net, flows, nflow, intr)
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DEC *net, **flows, *intr;
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int nflow;
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{
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int i;
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DEC dtemp, *temp=&dtemp, dooopi, *ooopi=&dooopi;
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DEC dtnet, *tnet=&dtnet, dpow, *pow=&dpow;
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_MacStart(GM_NPV);
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if (nflow<0) {
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_MacErr(GM_ARGVAL);
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_MacRet(GM_NULL);
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}
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_MacInVarD(intr);
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if (!flows||!net) {
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_MacErr(GM_NULLPOINTER);
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_MacRet(GM_NULL);
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}
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for (i=0;i<nflow;i++) {
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_MacInVarD(flows[i]);
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}
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if (CompareDecimal(intr,&decMinusHundred)!=1) {
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_MacErr(GM_ARGVAL);
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_MacRet(GM_NULL);
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}
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_MacDZero(tnet);
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_MacDCopy(temp, intr);
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temp->dc.id+=2;
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(void) _AddDec80Bit(temp, temp, &decOne);
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(void) _DivDec80Bit(ooopi, &decOne, temp);
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_MacDCopy(pow, (&decOne));
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for (i=0;i<nflow;i++) {
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(void) _MulDec80Bit(temp, flows[i], pow);
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(void) _AddDec80Bit(tnet, tnet, temp);
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(void) _MulDec80Bit(pow, pow, ooopi);
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}
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_ScaleDec80Bit(net, tnet, 2);
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_MacRet(net);
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}
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