Rather than having a toDouble method have a toPennies method which converts the string into an integer instead. This would make sure that there are no rounding issues and be a bit cleaner. BigDecimal would be another option but probably slightly more complicated.
Even better would be fix it all the way upstream but I’m guess that that probably isn’t an option.
Thomas
From: rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org]
On Behalf Of Yamil Bracho
Sent: 11 March 2010 19:00
To: Drools UserList
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Thomas, I am aware about this issue and it is my second item in the list to fix.
The only solution I got is convert all to String and this way works OK
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
Number( $total : doubleValue) from accumulate(
Map(this["_TYPE_"] == "D",
$monto : this["MONTO"]),
sum(toDouble($monto)))
$map : Map(this["_TYPE_"] == "H",
$totEnc : this["MT_TOTAL"]) &&
not (eval(isNumEquals($totEnc, $total)))
then
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El total de las lineas de detalle (" + formatDouble($total) +
") no empareja con lo del encabezado (" + formatDoubleObj($totEnc) + ")"));
end
function boolean isNumEquals(Object oNum1, double num2) {
return formatDoubleObj(oNum1).equals(formatDouble(num2));
}
function String formatDouble(double d) {
return (new DecimalFormat("#,###.00")).format(d);
}
function String formatDoubleObj(Object obj) {
return formatDouble(toDouble(obj));
}
The "isNumEquals" compare the numbers by comparing their String representations.
yes, I think this is not so elegant and I would like a better solutions...
Regards
From: TSwindells@nds.com
To: rules-users@lists.jboss.org
Date: Thu, 11 Mar 2010 16:17:05 +0000
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Well done for getting this working shame how complex it has to be. It would be nice/very very useful if drools provided a simple way of converting between numeric strings and numbers as I’ve also faced this problem before and it seems to require really big ugly hacks to work round the issue.
With respect to your solution I’d still reiterate the point I made in the post below about the fact that you may not get the result you are expecting,
As 0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1 != 1.0 you may get spurious error messages when you shouldn’t.
Thomas
From: rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org]
On Behalf Of Yamil Bracho
Sent: 11 March 2010 15:52
To: Drools UserList
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Thanks Enda.
Yes, I read carefully the docs and understand that eval expected a boolena expression.
I succesfully change the rule to :
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
Number( $total : doubleValue) from accumulate(
Map(this["_TYPE_"] == "D",
$monto : this["MONTO"]),
sum(toDouble($monto)))
$map : Map(this["_TYPE_"] == "H",
$totEnc : this["MT_TOTAL"]) &&
eval(toDouble($totEnc) != $total)
then
System.out.println("Encabezado:" + toDouble($totEnc) + ", Detalle=" + $total);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
Where "toDouble" is a function :
function double toDouble(Object oMonto) {
String strMonto = oMonto.toString();
int len = strMonto.length();
int pos = len - 2;
strMonto = StringUtils.left(strMonto, pos) + "." + StringUtils.right(strMonto,2);
//return Double.valueOf(strMonto) ;
double d = Double.parseDouble(strMonto);
return d;
}
Thanks to Enda and Thomas for help me to solve this...
Date: Thu, 11 Mar 2010 15:02:33 +0000
From: ejdiggins@gmail.com
To: rules-users@lists.jboss.org
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Hi Yamil,
'eval()' expects a primitive boolean value as a result of the expression. You may need to look into creating a custom accumulate function that can accept a string and do the conversion in java. Have a look at section 6.5.2.10.1 Accumulate Function in the Drools
documentation:
http://downloads.jboss.com/drools/docs/4.0.7.19894.GA/html_single/index.html
Alternatively, you could change the type of your map to something like Map<String, Double>
Hope it helps,
Enda
2010/3/11 Yamil Bracho <yamilbracho@hotmail.com>
I rewrote as :
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
Number( $total : doubleValue) from accumulate(
Map(this["_TYPE_"] == "D",
$monto : this["MONTO"]),
sum(eval(toDouble($monto))))
$map : Map(this["_TYPE_"] == "H",
this["MT_TOTAL"] != $total)
then
System.out.println("TOTAL=" + $total);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
Where "toDouble" is :
function Double toDouble(Object oMonto) {
String strMonto = oMonto.toString();
int len = strMonto.length();
int pos = len - 3;
strMonto = StringUtils.left(strMonto, pos) + "." + StringUtils.right(strMonto,2);
return Double.valueOf(strMonto) ;
}
And I got
Rule Compilation error : [Rule name='Sumatoria de lineas detalle vs Header']
rule/Rule_Sumatoria_de_lineas_detalle_vs_Header_0.java (9:1350) : The method eval(Double) is undefined for the type Rule_Sumatoria_de_lineas_detalle_vs_Header_0
Thanks again, Thomas..!
Date: Thu, 11 Mar 2010 09:25:31 +0000
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Have you tried assigning the string to $monto and then performing the evel within the sum?
From:
rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org]
On Behalf Of Yamil Bracho
Sent: 10 March 2010 19:38
To: Drools UserList
Subject: Re: [rules-users] Problems count and sumarizing data in facts
Thanks Thomas.
I rewrote the rule as:
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
Number( $total : doubleValue) from accumulate(
Map(this["_TYPE_"] == "D",
$monto : eval(Double.parseDouble(this.get("MONTO")))),
sum($monto))
$map : Map(this["_TYPE_"] == "H",
this["MT_TOTAL"] != $total)
then
System.out.println("TOTAL=" + $total);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
but I am getting errors in the parseDouble:
[828,29]: [ERR 101] Line 828:29 no viable alternative at input 'Double' in rule "Sumatoria de lineas detalle vs Header" in pattern Map[828,67]: [ERR 102] Line 828:67 mismatched input ')' expecting 'then' in rule "Sumatoria de lineas detalle vs Header"
Any hint...
From:
TSwindells@nds.com
To: rules-users@lists.jboss.org
Date: Wed, 10 Mar 2010 15:13:49 +0000
Subject: Re: [rules-users] Problems count and sumarizing data in facts
To convert from string to double you have to full back to java:
Something along the lines of
$monto : eval(Double.parseDouble(this.get(“MONTO”)))
However even with doing this your rules are unlikely to work consistently as you expect. Using equality tests on doubles is fundamentally unsafe as doubles aren’t represented
exactly and may not exactly match the value you think you have. Force instance 0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1 != 1.0 (dependent on floating point chipset etc). If you are dealing with currency then it is far simpler and safer to just operate with
integers and divide by 100 when you want to display the value. The other alternative is to use BigDecimal which will store an exact representation but will probably require more work with getting your accumulate function correct. Your last option is to use
Math.abs(left-right) < 0.1 to see if they are approximately equal. More details can be found here
http://firstclassthoughts.co.uk/java/traps/java_double_traps.html
Thomas
From:
rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org]
On Behalf Of Yamil Bracho
Sent: 10 March 2010 14:27
To: Drools UserList
Subject: Re: [rules-users] Problems count and sumarizing data in facts
I solved the counting of detail lines this way:
rule "Contador de lineas detalle vs Header"
salience 10
when
Number($count : intValue) from accumulate(
$mp : Map(this["_TYPE_"] == "D"), count($mp))
$map : Map(this["_TYPE_"] == "H",
this["NU_REGISTROS"] != $count)
then
System.out.println("NumRecs=" + $count);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"El número del lineas de detalle (" + $count +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
However, I still got problem with summarize the amounts. I wrote
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
Number( $total : doubleValue) from accumulate(
Map(this["_TYPE_"] == "D",
$monto : ((Number) this["MONTO"]),
sum($monto)))
$map : Map(this["_TYPE_"] == "H",
this["MT_TOTAL"] != $total)
then
System.out.println("TOTAL=" + $total);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
And i am getting mismatched input" so my question is how to convert a string to double in this line "$monto : ((Number) this["MONTO"])," ?
TIA
Yamil
From:
yamilbracho@hotmail.com
To: rules-users@lists.jboss.org
Date: Tue, 9 Mar 2010 17:41:43 +0000
Subject: [rules-users] Problems count and sumarizing data in facts
Hi, I have two kind of facts in a map.
There is a field called _TYPE_ (H)eader, D)etail)
In the Header line I have two String fields, one for the number of details lines ("NU_REGISTROS") and another for the sum of the detail line ("MT_TOTAL")
In the detail lines I only have a String field called "MONTO"
I would like to build two rules. One to check the count of detail lines versus the field in the header line so I wrote :
rule "Contador de lineas detalle vs Header"
salience 10
when
$numRecs : Number()
from accumulate(Map(this["_TYPE_"] == "D", $d : this["_NUMLINE_"]), count($d))
$map : Map(this["_TYPE_"] == "H",
this["NU_REGISTROS"] != $numRecs)
then
System.out.println("NumRecs=" + $numRecs);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
However I always got "NumRecs=1" when i print out the value of $numRecs but I am absolute sure there is two details lines...
Second when i try to sumarize the total field in the details line i got (MONTO in the detail line is a string):
rule "Sumatoria de lineas detalle vs Header"
salience 10
when
$total : Number()
from accumulate(Map(this["_TYPE_"] == "D",
$monto : this["MONTO"]),
sum(eval(Double.valueOf((String) $monto ))))
$map : Map(this["_TYPE_"] == "H",
this["MT_TOTAL"] != $total)
then
System.out.println("TOTAL=" + $total);
listBitacora.add(new BitacoraDTO($map.get("_NUMLINE_"),
"Error en el Detalle: El número del lineas de detalle (" + $total +
") no empareja con lo del encabezado (" + $map.get("NU_REGISTROS") + ")"));
end
but I got
Rule Compilation error : [Rule name='Sumatoria de lineas detalle vs Header']
rule/Rule_Sumatoria_de_lineas_detalle_vs_Header_0.java (9:1313) : The method eval(Double) is undefined for the type Rule_Sumatoria_de_lineas_detalle_vs_Header_0
Any help in those tow problems
TIA
Yamil
Actualízate gratis al nuevo Internet Explorer 8 y navega más seguro
Compartir tus mejores FOTOS es fácil en Messenger ¡DESCUBRE cómo!
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the
postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do
not print this e-mail unless necessary.
NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the
postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes.
To protect the environment please do not print this e-mail unless necessary.
An NDS Group Limited company. www.nds.com
¿Sabes que la Videollamada de Messenger es GRATIS ¡Descúbrela!
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the
postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes. To protect the environment please do
not print this e-mail unless necessary.
NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the
postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes.
To protect the environment please do not print this e-mail unless necessary.
An NDS Group Limited company. www.nds.com
¿Quieres saber qué móvil eres? ¡Descúbrelo aquí!
_______________________________________________
rules-users mailing list
rules-users@lists.jboss.org
https://lists.jboss.org/mailman/listinfo/rules-users
--
Enda J Diggins
Actualízate gratis al nuevo Internet Explorer 8 y navega más seguro
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster@nds.com and delete it from your system as well as any copies. The content of e-mails as well as traffic data
may be monitored by NDS for employment and security purposes. To protect the environment please do not print this e-mail unless necessary.
NDS Limited. Registered Office: One London Road, Staines, Middlesex, TW18 4EX, United Kingdom. A company registered in England and Wales. Registered no. 3080780. VAT no. GB 603 8808 40-00
**************************************************************************************
This message is confidential and intended only for the addressee. If you have received this message in error, please immediately notify the postmaster@nds.com and
delete it from your system as well as any copies. The content of e-mails as well as traffic data may be monitored by NDS for employment and security purposes.
To protect the environment please do not print this e-mail unless necessary.
An NDS Group Limited company. www.nds.com
¿Quieres saber qué móvil eres? ¡Descúbrelo aquí!