HP 48gII Advanced User's Reference Manual page 339

The sum of a binary integer and a real number is a binary integer that is the sum of the two
arguments, truncated to the current wordsize. (The real number is converted to a binary integer
before the addition.)
The sum of two binary integers is truncated to the current binary integer wordsize.
The sum of two unit objects is a unit object with the same dimensions as the second argument.
The units of the two arguments must be consistent.
The sum of two graphics objects is the same as the result of performing a logical OR, except that
the two graphics objects must have the same dimensions.
Common usage is ambiguous about some units of temperature. When ºC or ºF represents a
thermometer reading, then the temperature is a unit with an additive constant: 0 ºC = 273.15 K,
and 0ºF = 459.67ºR. But when ºC or ºF represents a difference in thermometer readings, then the
temperature is a unit with no additive constant: 1 ºC=1 K and 1 ºF =1 ºR.
The calculator assumes that the simple temperature units x_ºC and x_ºF represent thermometer
temperatures when used as arguments to the functions <, >, , , ==, and . This means that, in
order to do the calculation, the calculator will first convert any Celsius temperature to Kelvins
and any Fahrenheit temperature to Rankines. (For other functions or compound temperature units,
such as x_ºC/min, the calculator assumes temperature units represent temperature differences,
so there is no additive constant involved, and hence no conversion.) The arithmetic operators +,
–, %CH, and %T treat temperatures as differences, without any additive constant, but require
both arguments to be either absolute (K and ºR), both ºC, or both ºF. No other combinations
are allowed.
+
Access:
Flags: Numerical Results (-3), Binary Integer Wordsize (-5 through -10)
Input/Output:
See also: –, *, /, =, ADD
Level 2/Argument 1 Level 1/Argument 2
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1
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z
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Full Command and Function Reference 3-221
Level 1/Item 1
z + z
1 2
[ array ]
3
'z +symb'
'symb +z'
'symb + symb '
1 2
{ list list }
1 2
{ obj obj ... obj }
A 1 n
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1 n A
"string string "
1 2
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#n
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#n
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#n
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(x + y)_unit
2 2
'symb + x_unit'
'x_unit + symb'
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