The QUANTIZE function returns a decimal floating-point value that is equal in value (except for any rounding) and sign to numeric-expression and that has an exponent equal to the exponent of exp-expression.

The number of digits (16 or 34) is the same as the number of digits in numeric-expression.

The schema is SYSIBM.

numeric-expression

An expression that returns a value of any built-in numeric data type.
If the argument is not a decimal floating-point value, it is converted to DECFLOAT(34) for processing.

exp-expression

An expression that returns a value of any built-in numeric data type.
If the argument is not a decimal floating-point value, it is converted to DECFLOAT(34) for processing.
The exp-expression is used as an example pattern for rescaling numeric-expression.
The sign and coefficient of exp-expression are ignored.

The coefficient of the result is derived from that of numeric-expression.
It is rounded, if necessary (if the exponent is being increased), multiplied by a power of ten (if the exponent is being decreased), or remains unchanged (if the exponent is already equal to that of exp-expression).

The CURRENT DECFLOAT ROUNDING MODE special register determines the rounding mode.

Unlike other arithmetic operations on the decimal floating-point data type, if the length of the coefficient after the quantize operation is greater than the precision specified by exp-expression, the result is NaN and a warning is returned (SQLSTATE 0168D).
This ensures that, unless there is a warning condition, the exponent of the result of QUANTIZE is always equal to that of exp-expression.

• if either argument is NaN, NaN is returned
• if either argument is sNaN, NaN is returned and a warning is returned (SQLSTATE 01565)
• if both arguments are infinity (positive or negative), infinity with the same sign as the first argument is returned
• if one argument is infinity (positive or negative) and the other argument is not infinity, NaN is returned and a warning is returned (SQLSTATE 0168D)

The result of the function is a DECFLOAT(16) value if both arguments are DECFLOAT(16).
Otherwise, the result of the function is a DECFLOAT(34) value.
The result can be null; if any argument is null, the result is the null value.

Examples

1. The following examples show the values that are returned by the QUANTIZE function given a variety of input decimal floating-point values and assuming a rounding mode of ROUND_HALF_UP:

      QUANTIZE(2.17, DECFLOAT(0.001))    = 2.170 
      QUANTIZE(2.17, DECFLOAT(0.01))     = 2.17 
      QUANTIZE(2.17, DECFLOAT(0.1))      = 2.2 
      QUANTIZE(2.17, DECFLOAT('1E+0'))   = 2 
      QUANTIZE(2.17, DECFLOAT('1E+1'))   = 0E+1 
      QUANTIZE(2,    DECFLOAT(INFINITY)) = NaN    -- warning 
      QUANTIZE(0,    DECFLOAT('1E+5'))   = 0E+5 
      QUANTIZE(217,  DECFLOAT('1E-1'))   = 217.0 
      QUANTIZE(217,  DECFLOAT('1E+0'))   = 217 
      QUANTIZE(217,  DECFLOAT('1E+1'))   = 2.2E+2 
      QUANTIZE(217,  DECFLOAT('1E+2'))   = 2E+2

2. In the following example the value -0 is returned for the QUANTIZE function.
   The CHAR function is used to avoid the potential removal of the minus sign by a client program:

      CHAR(QUANTIZE(-0.1, DECFLOAT(1))) = -0