How should I parse this sentence?

Question

IEEE 754-1985 section 7.4(Underflow) says

After rounding - when a nonzero result computed as though the exponent range were unbounded would lie strictly between K(which is some value).

The following is my interpretation.

when a nonzero result computed as thought the exponent range unbounded is adverb clause.
would lie is verb phrase.
strictly between K is prepositional phrase.

So, when removing adverb clause and prepositional phrase, only verb remains there is no subject. Therefore my thought is wrong. What structure is used and what does it mean?

Answer 1

This is not a sentence at all, it's an adverbial clause. As an entry in a bulleted list, it should be combined with the introductory sentence fragment: "Tininess may be detected ..."

The completed sentence is then:

Tininess may be detected after rounding - when a nonzero result computed as though the exponent range were unbounded would lie strictly between +/- k.

The fragment "computed as though the exponent range were unbounded" is a restrictive clause, and would be clearer if set off by commas and marked with "that is." This does not change the parsing of the sentence.

Tininess may be detected after rounding - when a nonzero result, that is computed as though the exponent range were unbounded, would lie strictly between +/- k.

The sentence should be understood like this:

• If one makes a calculation,
• ... by assuming an unbounded exponent range,
• ... and gets a nonzero result,
• ... and rounds the result,
• ... and the result is between +/- k,
• ... then that result is called "tiny."