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RATIO - Ratio between two numbers and its error

Overview

Calculates the ratio between two independent numbers of events, and its error.

For a and b, that have statistical errors, sqrt(a) and sqrt(b),
ratio = a/b, and
error = a/b sqrt(1/a + 1/b)

Stack/Registers/Flags

StackBeforeAfter
t-destroyed
z-destroyed
yaerror on ratio
xbratio, a/b

No registers are used.
No flags are used.

Program

v1.00 May 20, 1991

    00   { 22-Byte Prgm }              ;                                        
    01   LBL "RATIO"                   ;                                        
    02   ENTER                         ; (x,y,z)=(b,b,a)                                       
    03   1/X                           ;                                        
    04   RCL  ST Z                     ; (a, 1/b, b, a)                                      
    05   1/X                           ; (1/a, 1/b, b, a)                                       
    06   +                             ; (1/a+1/b, b, a)                                       
    07   SQRT                          ; (sqrt(1/a+1/b), b, a)                                      
    08   Rv                            ; (b, a, *, sqrt)                                       
    09   /                             ; (a/b, *, sqrt)                                       
    10   ENTER                         ; (a/b, a/b, *, sqrt)                                       
    11   R^                            ; (sqrt, a/b, a/b, *)                        
    12   x                             ; (sqrt*a/b, a/b, *)                                       
    13   X<>Y                          ; (a/b, error)                                       
    14   END                                                                    
			

Programmed by Taku Yamanaka, May 20, 1991.