Returns a Number

Each function in Table 6.4 returns a number.

Table 6.4: XPath 1.0 functions that return a number
Open table as spreadsheet

Function	Meaning
ceiling(number)	Returns the value of a numeric expression, rounded upward to the greater integer. Here are examples:
	Invocation		Returns
	ceiling(2)		2
	ceiling(2.01)		3
	ceiling(-2)		2
	ceiling(-2.01)		-2
	ceiling(-2.99)		-2
count(node set)	Returns the number of nodes in a node set. Given our main example, the following expression resolves to 5. count(/descendant::Vehicle[Make])
floor(number)	Returns the value of a numeric expression, rounded downward to the lesser integer. Here are examples:
	Invocation		Returns
	floor(2)		2
	floor(2.99)		2
	floor(-2)		-2
	floor(-2.01)		-3
	floor(-2.99)		-3
last()	Returns the context size, as described earlier. In our main example, the value of last() in the following expression is 2. (/Insured/CarPolicy/Vehicle[2]/Make)[last()]
round(number)	Returns the value of a numeric expression, rounded to the nearest integer. The next examples show the effect of mid points.
	Invocation	Returns
	round(2.499)	2
	round(2.5)	3
	round(-2.5)	-2
	round(-2.501)	-3
string-length(string)	Returns the number of characters in the argument. Given our example, the following invocation returns 5(the number of letters in Honda). string-length(/descendant::Make[1])
sum(node set)	Returns the sum of the numeric values in each node in a node set. If the node includes non-numeric text, the returned value is NaN (not a number). Consider the following XML source <?xml version="1.0"?> <Options> <Towing>50</Towing> <Rental>20</Rental> </Options> The following expression resolves to 70. sum(/Options/*)