Bash AWK and Regex Apply on specific Column - regex

Question

I have the following dataset
Name,quantity,unit
car,6,6
plane,7,5
ship,2,3.44
bike,8,7.66
I want to print only the names which has unit in whole numbers.
I have done the following which does not give out the result
#!/bin/bash
awk 'BEGIN {
FS=","
}
/^[0-9]*$/ {
print "Has Whole numbers: " $1
}
' file.csv
The result should be
Has Whole numbers: car
Has Whole numbers: plane

Answer 1

Added a couple of lines to your test data:
Name,quantity,unit
car,6,6
plane,7,5
ship,2,3.44
bike,8,7.66
Starship,1,1.0
Super Heavy,2,0
null,0,
And awk:
$ awk -F, 'int($3)==$3 ""' file
Output:
car,6,6
plane,7,5
Super Heavy,2,0
int($3) makes an integer of $3 and $3 "" turns $3 to a string.

Answer 2

If you are sure 3rd column is a number:
awk -F, '(NR != 1 && $3 !~ /\./){print "Has Whole numbers:", $1}' file.csv
or well actually its better the way you did it:
awk -F, '$3 ~ /^[0-9]$/{print "Has Whole numbers:", $1}' file

Answer 3

Try changing /^[0-9]*$/ to $3 ~ /^[0-9]*$/ && $3 != 0 once in your tried attempt it should work then.
In case you DO NOT want to hard code field number and want to find out unit field number automatically then try following.
awk -F="," -v field_val="unit" '
FNR==1{
for(j=1;j<=NF;j++){
if($j==field_val){
field_number=j
next
}
}
}
$field_number ~ /[0-9]*$/ && $field_number!=0{
print "Has whole numbers: " $1
}' Input_file