Add two decimal number in bash script [duplicate]

Question

How can I add two decimal number in bash?? For instance this

LAT=37.748944
LNG=-122.4175548
D=0.01

somecommand --position "$(( LAT + D )), $(( LNG + D ))"

fails with

37.748944: syntax error: invalid arithmetic operator (error token is ".748944")

Answer 1

You can use bc, it should work with decimal calculations:

LAT=37.748944
LNG=-122.4175548
D=0.01

somecommand --position "$(echo "$LAT + $D" | bc), $(echo "$LNG + $D" | bc)"