Test integerness
Given a real numeric value, test whether or not it is an integer.
Test integerness is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
J
<lang J>(= <.) 3.14 7</lang>
- Output:
0 1
Perl 6
<lang perl6>say pi.narrow ~~ Int; say 1e5.narrow ~~ Int;</lang>
- Output:
False True
Python
<lang python>>>> def isint(f):
return int(f) == f
>>> isint(3.14) False >>> isint(3.0) True >>> </lang>
Tcl
The simplest method of doing this is testing whether the value is equal to the value after casting it to a integral value. <lang tcl>proc isNumberIntegral {x} {
expr {$x == entier($x)}
} foreach x {3.14 7 1000000000000000000000} {
puts [format "%s: %s" $x [expr {[isNumberIntegral $x] ? "yes" : "no"}]]
}</lang>
- Output:
3.14: no 7: yes 1000000000000000000000: yes