Suppressing the Decimal point

[Andre Jacobs]

I am doing a Celsius to Fahrenheit conversion,
the problem is that the converted figure must include only 2 characters beyond the decimal point (if any) and nothing if there are no decimals.

With the code below, it is doable, except that when the answer is a whole number (No decimals), then it still displays the decimal point.
How can I suppress the decimal point in this case?

Examples:-
Format$(35.1234, "####.##") ' gives "35.12" - fine
Format$(35.1, "####.##") ' gives "35.1" - fine
Format$(35, "####.##") ' gives "35." - Not fine, must give "35" (with no decimal point)

        Case %wm_command
            Select Case As Long Cb.Ctl
                Case %IDC_BUTTON3              ' Convert from C to F
                    Control Get Text Cb.Hndl, %IDC_TEXTBOX1 To sTxt$
                    sFmTxt$ = Str$((9/5)*(Val(sTxt$))+32)
                    Control Set Text Cb.Hndl, %IDC_TEXTBOX2, Format$(Val(sFmTxt$), "####.##")

                Case %IDC_BUTTON4              ' Convert from F to C
                    Control Get Text Cb.Hndl, %IDC_TEXTBOX2 To sTxt$
                    sFmTxt$ = Str$((5/9)*(Val(sTxt$)-32))
                    Control Set Text Cb.Hndl, %IDC_TEXTBOX1, Format$(Val(sFmTxt$), "####.##")

            End Select ' Cb.Ctl

[Dave Stanton]

A$=Format$(Val(sFmTxt$), "####.##")
If Right$(A$,1)="." then A$=A$(1,Len(A$)-1)
Control Set Text Cb.Hndl, %IDC_TEXTBOX2, A$

[Andre Jacobs]

Thanks, Dave

I thought there was a method with format$ or something similar, but your solution is elegant enough.

[Arie Verheul]

Or try the following

    Local A As Single
    Local FormatString As String
   
    A = 35.1783744
  
    A = Round(A,2)       ' Round to the desired number of digits
    
    FormatString = IIf$(Frac(A) = 0, "##", "##.##")     ' Test for decimals
    
    Print Using$(FormatString,A)

Arie Verheul

[Dave Biggs]

Remove$ the decimal point!

Control Set Text Cb.Hndl, %IDC_TEXTBOX2, Remove$(Format$(sFmTxt$, "0.00"), ".00")

[Andre Jacobs]

Thank you fellows,

You got my brain turning over again, with the nudges in the right direction

I ended up with:

Control Get Text Cb.Hndl, %IDC_TEXTBOX1 To sTxt$
sFmTxt$ = Str$((9/5)*(Val(sTxt$))+32)
Control Set Text Cb.Hndl, %IDC_TEXTBOX2, RTrim$(Format$(Val(sFmTxt$), "##.##"), ".")

serves my purpose just fine

[Michael Mattias]

These work good for money.... which by sheer good luck (yours) I choose to display with two decimals..

MACRO fmt_money (curval) = RSET$(FORMAT$(curval, "$#,.00"),12)
MACRO fmt_money2 (curval)= RSET$(FORMAT$(curval, "$#,.00 ;$#,.00-"),12) ' gives '0' in dollar position
MACRO fmt_money3 (curval)= RSET$(FORMAT$(curval, "$#,.00 ;$#,.00-; "),12) ' gives 'blank when zero'

[Mike Doty]

Money:
? USING$("#.##",Pennies&/100)
Noticed Michael's second and third macro put negative sign in the back and the first macro puts the negative sign in the front.
If the number is positive there is a trailing space in the 2nd and third macro.
USING$ with LONGs never have a rounding issue, only a range limitation.

[Michael Mattias]

MACRO fmt_number (X) = FORMAT$(X, IIF$(has_decimals, "#.##", "#"))

[Mike Doty]

has_decimals not defined

[Michael Mattias]

>has_decimals not defined

No, it isn't. I figured any rookie could handle that.

[Mike Doty]

#COMPILE EXE
#DIM ALL
MACRO fmt_number (X, has_decimals) = FORMAT$(X, IIF$(has_decimals, "#.##", "#"))
FUNCTION PBMAIN () AS LONG
? fmt_number(9.01,1)
END FUNCTION

[John Montenigro]

Just curious - would this be an improvement? It would avoid having the caller determine and tell the function whether the number "has_decimals"...
-jhm

MACRO fmt_number (X) = FORMAT$(X, IIF$(INSTR(X,"."), "#.##", "#"))

FUNCTION PBMAIN () AS LONG
  ? fmt_number(YourNumber)
END FUNCTION

[Mike Doty]

No.
It doesn't compile.
The purpose is to tell the function which way you want the result.

[Michael Mattias]

MACRO has_decimals (num) =  FIX(num) <> num

[John Montenigro]

No.
It doesn't compile.
The purpose is to tell the function which way you want the result.

Got it to compile by inserting the STR$() conversion.

MACRO fmt_number (X) = FORMAT$(X, IIF$(INSTR(STR$(X),"."), "#.##", "#"))

Difference in coding style? I'd rather the program figure out what's needed from what's there, rather than me having to know and tell it...

[Mike Doty]

No, it is not a difference in coding style.
The program doesn't know what function to use.
If you always want your number one way, one function is all that is needed.
Michael wrote the MACRO has_decimals to give you the ability to call any function.

#COMPILE EXE
#DIM ALL
MACRO has_decimals (num) =  FIX(num) <> num
MACRO fmt_number (X) = FORMAT$(X, IIF$(INSTR(STR$(X),"."), "#.##", "#"))
FUNCTION PBMAIN () AS LONG
  LOCAL num AS SINGLE
  num = 123.456      'answer rounded
  num = 123
 
'The program doesn't know if you want a whole number unless you tell it
'That is why Michael gave you another macro function
  IF has_decimals(num) THEN
    ? fmt_number(num)
  ELSE
    ? "Do you want it in another format?
  END IF
  SLEEP 3000
END FUNCTION

[Michael Mattias]

Actually I wrote it so you never have to test the number for decimals in-line at all:

MACRO has_decimals (num) = FIX(num) <> num 
MACRO Fmt_num (num)       = FORMAT$ (num, IIF$(has_decimals(num), "##.##", "#")) 
...
 
   PRINT fmt_num(num)   ' prints with decimals if it has any else without.

I was just trying to show how combining FORMAT$ with IIF$ can make your life easy.

Apparently not as desireable a goal as I had thought; "The long, hard way" remains immensely popular. (see also: http://www.powerbasic.com/support/pb...ad.php?t=39710)

MCM