With Perl you can check if an array contains a value
$ perl -e '@foo=(444,555,666); print 555 ~~ @foo ? "T" : "F"'
T
However with awk, this similar command is checking the array indexes rather than values
$ awk 'BEGIN {split("444 555 666", foo); print 555 in foo ? "T" : "F"}'
F
How can I check if an array contains a particular value with awk?
Awk noob here. I digested Steven's answer and ended up with this hopefully easier to understand snippet below. There are 2 more subtle problems:
["value1", "value2"], it's more like {0: "value1", 1: "value2"}.in checks for keys, and there is no built-in way to check for values.So you have to convert your array (which is actually a dictionary) to a dictionary with the values as keys.
BEGIN {
split("value1 value2", valuesAsValues)
# valuesAsValues = {0: "value1", 1: "value2"}
for (i in valuesAsValues) valuesAsKeys[valuesAsValues[i]] = ""
# valuesAsKeys = {"value1": "", "value2": ""}
}
# Now you can use `in`
($1 in valuesAsKeys) {print}
echo "A:B:C:D:E:F" | tr ':' '\n' | \
awk 'BEGIN{ split("A D F", parts); for (i in parts) dict[parts[i]]=""} $1 in dict'
what I do is structure my data to take advantage of what the language provides.
So instead of saying :
BEGIN {split("444 555 666", foo); .... }
say :
BEGIN { bar[ "444" ] ; ... }
or ala another suggestion:
BEGIN {
split("444 555 666", foo);
for( i in FOO ) bar[foo[i]];
}
remember arrays in awk are really associative arrays.
BEGIN {
split("value1 value2 value3", valueArray)
# valueArray is {1: "value1", 2: "value2", 3: "value2"}
}
{
# given $1 is the value to test for
for (i in valueArray) {
if ( $1 == valueArray[i] ) {
print $1
# OR
print "True"
# ...
}
}
}
In the spirit of a one-liner (see Thamme's answer) that sticks more to the OP's perl reference (ternary operator):
echo -e "a\nb\nc" | awk '{t[$1]}END{print (("a" in t) ? "yes":"no")}' # prints yes, try with ("m" in t)
gawk 'BEGIN { split("a b c d",parts); for (i in parts) dict[parts[i]]=1 } $1 in dict {print}' some.log
awk 'BEGIN { split("444 555 666", foo); for(i=1; i<=length(foo); i++) bar[foo[i]]; print 555 in bar ? "T" : "F" }'for( i in foo ) bar[foo[i]]instead?awk 'BEGIN { split("444 555 666", foo); for(i in foo) bar[foo[i]]; print 555 in bar ? "T" : "F" }'.