Test integerness: Difference between revisions

=={{header|jq}}==

{{works with|jq|1.4}}

jq does not have builtin support for complex numbers or rationals, but in conformity with

the Rosetta Code page [[Arithmetic/Complex#jq]], we shall assume in the following that the complex number x+iy

has been identified with the array [x,y]. To illustrate how the task can be solved for rationals,

we shall also identify the rational numbers p/q with JSON objects that have the form:

{"type": "rational", "p": p, "q": q}.

<lang jq>def is_integral:

if type == "number" then . == floor

elif type == "array" then

length == 2 and .[1] == 0 and (.[0] | is_integral)

else type == "object"

and .type == "rational"

and .q != 0

and (.q | is_integral)

and ((.p / .q) | is_integral)

end ;</lang>

'''Example''':

<lang jq>(

0, -1, [3,0], {"p": 4, "q": 2, "type": "rational"},

1.1, -1.1, [3,1], {"p": 5, "q": 2, "type": "rational"}

) | "\(.) => \(if is_integral then "integral" else "" end)"</lang>

{{out}}

<lang sh>$ jq -r -n -f is_integral.jq

0 => integral

-1 => integral

[3,0] => integral

{"p":4,"q":2,"type":"rational"} => integral

1.1 =>

-1.1 =>

[3,1] =>

{"p":5,"q":2,"type":"rational"} => </lang>