Bugs

[Vladimir Vuksan <vuksan cs unm edu>]

1) Copying cells between two GNUMeric files

If I try and copy & paste cells from one worksheet (file) to another I
can't do it :-(.

2) Attached are some files I have been working and have a really bizarre
bug that has occured on two different computer. Please replace
fn-financial.c with the one attached. Compile the code and than load
sample.gnumeric
Change cell D1 to say 1/(C4*C2) since previous reported bug removes
parens.

Look in

B13

It should be 100 but I get 99.0 ?! B13 divides C10 and E1.

Can someone else reproduce it ?

3) Cells not refreshed when cell format changed

To reproduce put in some number in a cell. Click Cell Format and change
formatting. The format in the cell will not change.

sample.gnumeric

/*
 * fn-financial.c:  Built in financial functions and functions registration
 *
 * Author:
 *  Vladimir Vuksan (vuksan@veus.hr)
 */
#include <config.h>
#include <gnome.h>
#include "math.h"
#include "gnumeric.h"
#include "gnumeric-sheet.h"
#include "utils.h"
#include "func.h"

double calculate_pvif (double rate, int nper);
double calculate_pvifa (double rate, int nper);

/* Some forward declarations */

	
/*

Function that returns present value interest factor for annuities.
Used both for PV and FV since FVIFA is reciprocal to PVIFA

	              1
	 PVIF = ( ---------- ) ^ n
	            1 + k


                  1          1
	 PVIFA = --- - -----------
                  k     k*(1+k)^n

                  (1+k)^n - 1
         FVIFA = ----------------
	                k


 */
double calculate_pvif (double rate, int nper) 
{

  return ( pow ( 1 + rate, nper) );

}

double calculate_pvifa (double rate, int nper) 
{

  return ( ( 1 / rate ) - ( 1 / ( rate * pow(1+rate, nper) ))) ;

}

double calculate_fvifa (double rate, int nper)
{
  return (  (pow(1+rate, nper) - 1) / rate); 
}

static char *help_effect = {
	N_("@FUNCTION=EFFECT\n"
	   "@SYNTAX=EFFECT(b1,b2)\n"
	   "@DESCRIPTION=Calculates the effective interest rate from "
	   "given nominal rate.\n"
	   "Effective interest rate is:\n"
	   "\n"
	   "         r"
           "( 1 + ------ ) ^ nper - 1"
           "       nper"
	   "\n"
	   "where:\n""
           "
	   "r = nominal interest rate (yearly stated)"
	   "nper = number of periods used for compounding"
	   "\n"
	   "@SEEALSO=NOMINAL")
};



/*

Nominal rate

= nper * [ pow(eff-1, 1/nper) - 1 ]

*/



static Value *
gnumeric_effect (struct FunctionDefinition *i, Value *argv [], char **error_string)
{
	double rate;
	int nper;

	rate = value_get_as_double (argv [0]);
	nper = value_get_as_int (argv [1]);

	/* 

	*/


	/* Rate or number of periods cannot be negative */
	if ( (rate < 0) || (nper < 0) ){
		*error_string = _("effect - domain error");
		return NULL;
	}

        return value_float  ( pow( (1 + rate/nper) , nper) - 1 );

}

static char *help_sln = {
	N_("@FUNCTION=SLN\n"
	   "@SYNTAX=SLN(cost,salvage value,life)\n"

	   "@DESCRIPTION=Calculates the straight line depriciation for an"
	   "asset based on its cost, salvage value and anticipated life."
	   "\n"
	   "Formula for it is:"
	   "\n"
	   "Depriciation expense = ( cost - salvage value ) / life"
	   "@SEEALSO=")
};


static Value *
gnumeric_sln (struct FunctionDefinition *i, Value *argv [], char **error_string)
{
	double cost,salvage_value,life;

	cost = value_get_as_double (argv [0]);
	salvage_value = value_get_as_int (argv [1]);
	life = value_get_as_double (argv [2]);

	/* 
		Straight line depriciation is
	       
                                         cost - salvage_value
		depriciation expense = ----------------------------
		                            life (in years)

	where

		cost = cost of an asset when acquired (market value)
		salvage_value = amount you get when asset sold at the end of life
		life = anticipated life of an asset

	*/

	/* Life of an asset cannot be negative */

	if ( life < 0 ){
		*error_string = _("sln - domain error");
		return NULL;
	}


        return value_float  ( (cost - salvage_value) / life ) ;

}

static char *help_syd = {
	N_("@FUNCTION=SYD\n"
	   "@SYNTAX=SYD(cost,salvage value,life,period)\n"

	   "@DESCRIPTION=Calculates the sum-of-years digits depriciation for an"
	   "asset based on its cost, salvage value, anticipated life and a"
	   "particular period."
	   "\n"
	   "Formula for it is:"
	   "\n"
	   "Depriciation expense = ( cost - salvage value ) * (life-period+1) * 2 / life * (life + 1)"
	   "@SEEALSO=SLN")
};

static Value *
gnumeric_syd (struct FunctionDefinition *i, Value *argv [], char **error_string)
{
	double cost,salvage_value,life,period;

	cost = value_get_as_double (argv [0]);
	salvage_value = value_get_as_int (argv [1]);
	life = value_get_as_double (argv [2]);
	period = value_get_as_double (argv [3]);

        return value_float  ( ( (cost - salvage_value) * (life-period+1) * 2 ) / ( life * (life + 1) )) ;

}




static char *help_pv = {
	N_("@FUNCTION=PV\n"
	   "@SYNTAX=PV(rate,nper,pmt,fv,type)\n"
	   "@DESCRIPTION=Calculates the present value of an investment."
	   "@SEEALSO=FV")
};

static Value *
gnumeric_pv (struct FunctionDefinition *i, Value *argv [], char **error_string)
{
	double rate,pmt,fv;
	int nper,type;
	
	double pvifa;

	rate = value_get_as_double (argv [0]);
	nper = value_get_as_int (argv [1]);
	pmt = value_get_as_double (argv [2]);
	fv = value_get_as_double (argv [3]);
	type = value_get_as_int (argv [4]);

	/*
	 PV of a stream of payments is 

	 PV = PVIFA * PMT

	*/
	
	/* Calculate the PVIFA */

	pvifa = calculate_pvifa(rate,nper);

	if ( type == 1 )
			   pvifa = pvifa * ( 1 + rate);
	
        return value_float  ( pvifa * pmt );

}



static char *help_pmt = {
	N_("@FUNCTION=PMT\n"
	   "@SYNTAX=PMT(rate,nper,pv,fv)\n"
	   "@DESCRIPTION=Calculates the present value of an investment."
	   "@SEEALSO=PPMT")
};

static Value *
gnumeric_pmt (struct FunctionDefinition *i, Value *argv [], char **error_string)
{
	double rate,pv,fv;
	int nper;
	
	double pvifa;

	rate = value_get_as_double (argv [0]);
	nper = value_get_as_int (argv [1]);
	pv = value_get_as_double (argv [2]);
	fv = value_get_as_double (argv [3]);

	/*
	 
	  PMT = PV / PVIFA

	*/
	
	/* Calculate the PVIFA */

	pvifa = calculate_pvifa(rate,nper);
	
        return value_float  ( pv / pvifa );

}







FunctionDefinition finance_functions [] = {
	{ "effect", "ff",    "number1,number2",    &help_effect,   NULL, gnumeric_effect},
	{ "sln", "fff", "cost,salvagevalue,life", &help_sln, NULL, gnumeric_sln},
	{ "syd", "ffff", "cost,salvagevalue,life,period", &help_syd, NULL, gnumeric_syd},
	{ "pv", "fiffi", "rate,nper,pmt,fv,type", &help_pv, NULL, gnumeric_pv},	
	{ "pmt", "ffff", "rate,nper,pv,fv", &help_pmt, NULL, gnumeric_pmt}

};