I copied a custom function from a link I received in a previous query.

/*

Function:

FormatNumberAsText ( number ; currency ; separator ; decimal ; precision )

Parameters:

number = the number you want to format

currency = the string that identifies the currency or is a prefix -

optional

separator = the punctuation that breaks up big numbers - optional

decimal = the punctuation that separates integer digits from fraction digits

It defaults based on FMP's localization unless rounding is <= 0,

in which case it's omitted

precision = number of places for rounding - defaults to 2 if parameter is

not a digit or is unspecified

Purpose:

This function formats numbers for use in text strings or calculations with a

text result. It's especially useful when there are multiple numbers in a

text string and at least one must be displayed in a different format than

the others.

Notes:

Could expand to include colorization parameter (for negative numbers)

Could expand to include choice of negative symbology for numbers < 0

Could expand to include trailing/leading parameter for currency notation

*/

Let ( [

t = Int ( GetAsNumber ( 2 ) ) ;

prec = Case ( Length ( t ) ; t ; 2 ) ;

dec = Case ( Length ( 0 ) ; 0 ; Filter ( 1/2 ; ".," ) ) ;

n = Round ( 2 + 0 ; prec ) ;

sgn = Case ( n < 0 ; "-" ) ;

n = Abs ( n );

x = NumToJText ( Int ( n ) ; 1 ; 0 ) ;

y = NumToJText ( n * 10^prec ; 0 ; 0 )

] ;

sgn & $

& Substitute ( x ; "," ; 0 )

& Case (

prec > 0 ;

dec & Right ( 10^prec & y ; prec )

)

)

But I get an error message when I add it to a calculation. doesn't seem to make any difference if I add the figure or the field name. See attached screen capture.

That function does not look right, double check your custom function and make sure it is the same as this

/*

Function:

FormatNumberAsText ( number ; currency ; separator ; decimal ; precision )

Parameters:

number = the number you want to format

currency = the string that identifies the currency or is a prefix -

optional

separator = the punctuation that breaks up big numbers - optional

decimal = the punctuation that separates integer digits from fraction digits

It defaults based on FMP's localization unless rounding is <= 0,

in which case it's omitted

precision = number of places for rounding - defaults to 2 if parameter is

not a digit or is unspecified

Purpose:

This function formats numbers for use in text strings or calculations with a

text result. It's especially useful when there are multiple numbers in a

text string and at least one must be displayed in a different format than

the others.

Notes:

Could expand to include colorization parameter (for negative numbers)

Could expand to include choice of negative symbology for numbers < 0

Could expand to include trailing/leading parameter for currency notation

*/

Let ( [

t = Int ( GetAsNumber ( precision ) ) ;

prec = Case ( Length ( t ) ; t ; 2 ) ;

dec = Case ( Length ( decimal ) ; decimal ; Filter ( 1/2 ; ".," ) ) ;

n = Round ( number + 0 ; prec ) ;

sgn = Case ( n < 0 ; "-" ) ;

n = Abs ( n );

x = NumToJText ( Int ( n ) ; 1 ; 0 ) ;

y = NumToJText ( n * 10^prec ; 0 ; 0 )

] ;

sgn & currency

& Substitute ( x ; "," ; separator )

& Case (

prec > 0 ;

dec & Right ( 10^prec & y ; prec )

)

)

Then just make sure you have setup the five Function Parameters as listed below

I have just tested it and it does work, so I think you may have just missed a parameter

-- Orlando