# System Functions

XOR( ) | Logical Exclusive OR

## Format

XOR(value1[$],value2[$][,ERR=stmtref])

Where:

stmtref | Program line number or statement label to which to transfer control.
value1[$] value2[$] | Compared values. String or numeric expressions/variables. If strings, value1$ must be the same length as value2$.

## Returns

Result of logical exclusive 'OR' comparison of two expressions/variables.

## Description

The XOR( ) function performs a bit-wise exclusive 'OR' comparison of two string or numeric expressions/variables and generates a value as a result. The length of the two string expressions must be equal or PxPlus returns an Error #46: Length of string invalid.

Binary | Result
0 XOR 0 | =0
0 XOR 1 | =1
1 XOR 0 | =1
1 XOR 1 | =0

Sample Comparison Results:

| XOR($41$,$42$) | yields Hex 03, 00000011
| XOR($41$,$25$) | yields Hex 64, 01100100
| XOR($5A$,$DD$) | yields Hex 87, 10000111

## See Also

IOR( ) Logical OR
AND( ) Logical AND

## Example

0040 read (1,end=1000)F$
0050 R$=xor(F$(1,2),$2020$) ! Convert to lowercase
0060 ...
if pos($00$=xor(ucs(X$),lcs(X$)))=0 then print X$," is all alpha!"