campo-sirio/gfm/mirr.c
alex ba237a9d91 Patch level : no patch
Files correlati     :
Ricompilazione Demo : [ ]
Commento            :
Aggiunti i sorgenti per Greenleaf Math Library (gfm.dll)


git-svn-id: svn://10.65.10.50/trunk@10079 c028cbd2-c16b-5b4b-a496-9718f37d4682
2002-02-26 12:19:02 +00:00

138 lines
2.9 KiB
C
Executable File

/* DEC *ModifiedIRR(irr, flows, nflow, intr, safe)
*
* ARGUMENT
* DEC *irr, **flows, *intr, *safe;
* int nflow;
*
* DESCRIPTION
* Calculates the modified int. rate of return of a series of cash flows.
* The nflow cash flows in the array flows are invested at interest
* rate intr for positive cash flows and borrows at interest rate safe
* for negative cash flows.
* The modified internal rate of return is calculated and stored in irr.
*
* SIDE EFFECTS
* None.
*
* RETURNS
* irr if successful, otherwise GM_NULL.
*
*
* POSSIBLE ERRORS
* GM_NULLPOINTER
* GM_ARGVAL
*
* AUTHOR
* Jared Levy
* Copyright (C) 1988-1990 Greenleaf Software Inc. All rights reserved.
*
* MODIFICATIONS
*
*
*/
#include <stdio.h>
#include "gm.h"
#include "gmsystem.h"
DEC *ModifiedIRR(irr, flows, nflow, intr, safe)
DEC *irr, **flows, *intr, *safe;
int nflow;
{
int i;
mbool wfNeg, wfPos;
DEC dtemp, *temp=&dtemp, dooopi, *ooopi=&dooopi;
DEC dpow, *pow=&dpow, dopi, *opi=&dopi;
DEC dnpvn, *npvn=&dnpvn, dnfvp, *nfvp=&dnfvp;
DEC *p;
_MacStart(GM_MIRR);
if (nflow<2) {
_MacErr(GM_ARGVAL);
_MacRet(GM_NULL);
}
_MacInVarD(intr);
_MacInVarD(safe);
if (!flows) {
_MacErr(GM_NULLPOINTER);
_MacRet(GM_NULL);
}
_MacOutVarD(irr);
/* check for null pointers, at least one pos & neg cash flow */
wfPos=FALSE;
wfNeg=FALSE;
for (i=0;i<nflow;i++) {
p = flows[i];
_MacInVarD(p);
wfPos=wfPos||_MacIsDecP(p);
wfNeg=wfNeg||_MacIsDecN(p);
}
if (!wfPos||!wfNeg) {
_MacErr(GM_ARGVAL);
_MacRet(GM_NULL);
}
if ((CompareDecimal(intr,&decMinusHundred)!=1)
||(CompareDecimal(safe,&decMinusHundred)!=1)) {
_MacErr(GM_ARGVAL);
_MacRet(GM_NULL);
}
/* calculate npv of negative values at safe rate */
_MacDZero(npvn);
_MacDCopy(temp, safe);
temp->dc.id+=2;
(void) _AddDec80Bit(temp, temp, &decOne);
(void) _DivDec80Bit(ooopi, &decOne, temp);
_MacDCopy(pow, (&decOne));
for (i=0;i<nflow;i++) {
if (_MacIsDecN(flows[i])) {
(void) _MulDec80Bit(temp, flows[i], pow);
(void) _AddDec80Bit(npvn, npvn, temp);
}
(void) _MulDec80Bit(pow, pow, ooopi);
}
/* calculate nfv of positive values at intr */
_MacDZero(nfvp);
_MacDCopy(temp, intr);
temp->dc.id+=2;
(void) _AddDec80Bit(opi, temp, &decOne);
_MacDCopy(pow, (&decOne));
for (i=nflow-1;i>=0;i--) {
if (_MacIsDecP(flows[i])) {
(void) _MulDec80Bit(temp, flows[i], pow);
(void) _AddDec80Bit(nfvp, nfvp, temp);
}
(void) _MulDec80Bit(pow, pow, opi);
}
/* calculate modified internal rate of return */
_MacDChgs(npvn);
(void) _DivDec80Bit(temp, nfvp, npvn);
(void) _LnDec80Bit(temp, temp);
(void) ConvLongToDecimal(pow, (long) (nflow-1));
(void) _DivDec80Bit(temp, temp, pow);
(void) _ExpDec80Bit(temp, temp);
(void) _SubDec80Bit(temp, temp, &decOne);
if (temp->dc.id>=2)
temp->dc.id -=2;
else {
ConvLongToDecimal(pow, 100L);
(void) _MulDec80Bit(temp, temp, pow);
}
(void) _Sq5UnsTo4Uns(temp);
_MacDCopy(irr,temp);
_MacRet(irr);
}