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hi,
why this code
Code:
``` EXPORT provasol() BEGIN local yield, coupon, ann, years, price; coupon:=6.75; ann:=2; years:=14; price:=122.125; yield := Solve.SOLVE((coupon/ann)*( (1-1/(1+(X/ann))^(ann*years)) / (X/ann) ) + 100/(1+(X/ann))^(ann*years) = price, X); RETURN yield; END;```

If I try with the values in Home I get the correct answer: 0.0459035...
Code:
``` Solve.SOLVE((6.75/2)*( (1-1/(1+(X/2))^(2*14)) / (X/2) ) + 100/(1+(X/2))^(2*14) = 122.125, X);```

Thank you
Salvo
Hi Salvo;

The program's local vars don't persist within the Solve app (out of scope). If you use Globals (see the reserved vars in the code below), the program works fine.

<<A subroutine *could* be used to pass locals to reserved vars, and return the results back to yield, if necessary.>>

Code:
``` EXPORT provasol() BEGIN   local yield, coupon, ann, years, price; // Using reserved vars as globals   C:=6.75;   A:=2;   Y:=14;   P:=122.125; //  Locals don't persist in Solve App   //coupon:=6.75;   //ann:=2;   //years:=14;   //price:=122.125;   //yield := Solve.SOLVE((coupon/ann)*( (1-1/(1+(X/ann))^(ann*years)) / (X/ann) ) + 100/(1+(X/ann))^(ann*years) = price, X);      yield := Solve.SOLVE((C/A)*( (1-1/(1+(X/A))^(A*Y)) / (X/A) ) + 100/(1+(X/A))^(A*Y) = P, X);   RETURN yield; END;```
(05-31-2015 10:31 AM)DrD Wrote: [ -> ]Hi Salvo;

The program's local vars don't persist within the Solve app (out of scope). If you use Globals (see the reserved vars in the code below), the program works fine.

<<A subroutine *could* be used to pass locals to reserved vars, and return the results back to yield, if necessary.>>

thank you!
It works.

I'm using it in the first version for my program to calc Bonds (for now, however, this one, with the flag to calculate "financial year" -30/360- gives result for price a little different from the 12C, and sure my formulas aren't correct, and the Prime reset calculating yield for this option: please, try, advice...)

here there are the code:
Code:
``` EXPORT Bonds() BEGIN END; EXPORT Price() BEGIN   local mesg, days1, days2, toReg, N, finAct;   local sd, sm, sy, md, mm, my, ann;   local coupon, yi, years, price, inter, dayPer;   input ({ {sd,[0],{15,15,1}},    {sm,{"1","2","3", "4", "5", "6", "7", "8", "9", "10", "11", "12"}, {40,15,1}},    {sy,[0],{70,20,1}},   {md,[0],{15,15,2}},    {mm,{"1","2","3", "4", "5", "6", "7", "8", "9", "10", "11", "12"}, {40,15,2}},    {my,[0],{70,20,2}},   {coupon,[0],{40,15,4}}, {yi,[0], {75,15,4}},   {ann,[0], {40,15,5}}, {finAct,2,{85,2, 5}}   },    "Price of Bond (maturity 100)", {"sd", "sm", "sy", "md", "mm", "my",    "Coupon", "y%", "ann", "Financial"},    {"Settlement day", "Settlement month", "Settlement year (purchase)",    "Maturity day", "Maturity month", "Maturity year (regulation)",    "Coupon payment %", "yield %", "n. of annuality (i.e 2=semi)", "Financial year (360)"},    {1, 0, 0, 1, 0, 0, 0, 0, 0, 0 }, {1, 0, 2015, 1, 0, 2015, 6.75, 4.75, 2, 0} );   sd:=EVAL(sd); sm:=EVAL(sm);   md:=EVAL(md); mm:=EVAL(mm);   sy:=EVAL(sy); my:=EVAL(my);   days1 := sy+sm/100+sd/10000;   days2 := my+mm/100+md/10000;   toReg := sy+mm/100+md/10000; // days to the regulation   years := my-sy; // years to the maturity   IF years==0 THEN years:= 1; END;   IF (finAct==0) THEN   N:= DDAYS(days1, days2);   toReg := DDAYS(days1, toReg);   dayPer := IP(365/ann);   ELSE   N:= 30*(mm-sm)+md-sd;   toReg:= 30*(mm-sm)+md-sd;   dayPer:= 360/ann;   END; // if   price := (coupon/ann)*( (1-1/(1+(yi/(ann*100)))^(ann*years)) / (yi/(ann*100)) ) + 100/(1+(yi/(ann*100)))^(ann*years);   inter := (coupon/ann)*((dayPer - toReg)/dayPer);   RECT_P();   TEXTOUT_P("Days: " + N + " to the end (" + years + " years)", 10, 50);   TEXTOUT_P("from " + sd + "-" + sm + "-" + sy + " to " + md + "-" + mm + "-" + my , 10, 65 );   TEXTOUT_P("Price of Bond: " + price, 10, 85);   TEXTOUT_P("Paid " + ann + " times per year", 10, 105);   TEXTOUT_P("Interest: " + inter, 10, 125);   TEXTOUT_P("Press ESC to continue", 10, 150);   WAIT;   RETURN {ROUND(price, 3), ROUND(inter,3), ROUND(price+inter,3)}; END; EXPORT Yield() BEGIN   local mesg, days1, days2, toReg, N, finAct;   local sd, sm, sy, md, mm, my, years, yield;   local coupon, price, ann, inter, dayPer;   input ({ {sd,[0],{15,15,1}},    {sm,{"1","2","3", "4", "5", "6", "7", "8", "9", "10", "11", "12"}, {40,15,1}},    {sy,[0],{70,20,1}},   {md,[0],{15,15,2}},    {mm,{"1","2","3", "4", "5", "6", "7", "8", "9", "10", "11", "12"}, {40,15,2}},    {my,[0],{70,20,2}},   {coupon,[0],{40,15,4}}, {price,[0], {75,15,4}},   {ann,[0], {40,15,5}}, {finAct,2,{85,2, 5}}   },    "Bond YTM: yield to maturity", {"sd", "sm", "sy", "md", "mm", "my",    "Coupon", "Price", "annu", "Financial"},    {"Settlement day", "Settlement month", "Settlement year (purchase)",    "Maturity day", "Maturity month", "Maturity year (regulation)",    "Coupon payment %", "Price now", "n. of annuality (i.e 2=semi)", "Financial year (360)"},    {1, 0, 0, 1, 0, 0, 0, 0, 0, 0 }, {1, 0, 2015, 1, 0, 2015, 6.75, 120, 2, 0} );   sd:=EVAL(sd); sm:=EVAL(sm);   md:=EVAL(md); mm:=EVAL(mm);   sy:=EVAL(sy); my:=EVAL(my);   days1 := sy+sm/100+sd/10000;   days2 := my+mm/100+md/10000;   toReg := sy+mm/100+md/10000; // days to the regulation   years := my-sy; // years to the maturity   IF years==0 THEN years:= 1; END;   IF (finAct==0) THEN   N:= DDAYS(days1, days2);   toReg := DDAYS(days1, toReg);   dayPer := IP(365/ann);   ELSE   N:= 30*(mm-sm)+md-sd;   toReg:= 30*(mm-sm)+md-sd;   dayPer:= 360/ann;   END; // if   C:= coupon; A:= ann; Y:= years; P:= price;   yield := Solve.SOLVE((C/A)*( (1-1/(1+(X/A))^(A*Y)) / (X/A) ) + 100/(1+(X/A))^(A*Y) = P, X);   RECT_P();   TEXTOUT_P("Days: " + N + " to the end (" + years + " years)", 10, 50);   TEXTOUT_P("from " + sd + "-" + sm + "-" + sy + " to " + md + "-" + mm + "-" + my , 10, 65 );   TEXTOUT_P("Price of Bond: " + price, 10, 85);   TEXTOUT_P("Paid " + ann + " times per year", 10, 105);   TEXTOUT_P("Yield to Maturity: " + ROUND(100*yield,3) + "%", 10, 125);   TEXTOUT_P("Press ESC to continue", 10, 150);   WAIT;   RETURN ROUND(100*yield,3); END;```
I'd also recommend using FNROOT instead. That is the normal root finder routine that is not an app function.
(06-01-2015 04:04 PM)Tim Wessman Wrote: [ -> ]I'd also recommend using FNROOT instead. That is the normal root finder routine that is not an app function.

Thank you Tim, I'll try it soon for my program!

Salvo
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