2.1.3 [W3C-XSD] Section 3.2.4, float
The specification states:
[Definition:] float is patterned after the IEEE single-precision 32-bit floating point type [IEEE 754-1985]. The basic ·value space· of float consists of the values m × 2^e, where m is an integer whose absolute value is less than 2^24, and e is an integer between -149 and 104, inclusive. In addition to the basic ·value space· described above, the ·value space· of float also contains the following three special values: positive and negative infinity and not-a-number (NaN). The ·order-relation· on float is: x < y iff y - x is positive for x and y in the value space. Positive infinity is greater than all other non-NaN values. NaN equals itself but is ·incomparable· with (neither greater than nor less than) any other value in the ·value space·.
No error is reported if the
NaN value is compared with positive infinity or negative infinity.