This is a popup calculator originally written by Finn Kristensen in 2000.

It's been patched up a bit over the years, and I've cleaned it up for DF 19.1

Code:
  on_key KEY_CTRL+KEY_L send activate_fkCalc
allows you to start with a hot_key

or you can us it as a prompt

Code:

Code:
       Object oDealBill_PPG_charged is a dbForm
            Entry_Item DealBill.PPG_charged
            Set Location to 19 242
            Set Size to 13 78
            Set Label to "Dlr Price PG:"
            Set Label_Justification_Mode to JMode_Top
            Set Label_Col_Offset to 0
            Set Prompt_Button_Mode to PB_PromptOn
            Set Prompt_Object to ghocalculator
        End_Object

FKCALC.PKG
MM