AWK to find average rainfall in three states

Question

I want to find the average rainfall in three states, for example, CA, TX and AX for a particular month from January to December. This input file is limited TAB SPACESand has a format city name, the state , and then average rainfall amounts from January through December, and then an annual average for all months. EG may look like

AVOCA   PA  30  2.10    2.15    2.55    2.97    3.65    3.98    3.79    3.32     3.31   2.79    3.06    2.51    36.18
BAKERSFIELD CA  30  0.86    1.06    1.04    0.57    0.20    0.10    0.01    0.09    0.17    0.29    0.70    0.63    5.72

What I want to do is "Get the sum of the average rainfall for a given month feb, for more than n years, and then find the average value for the states CA, TX and AX.

I wrote below script in awk to do the same, but it does not give me the expected output

/^CA$/ {CA++; CA_SUM+= $5} # ^CA$ - Regular Expression to match the word CA only 
/^TX$/ {TX++; TX_SUM+= $5} # ^TX$ - Regular Expression to match the word TX only  
/^AX$/ {AX++; AX_SUM+= $5} # ^AX$ - Regular Expression to match the word AX only 
END {
     CA_avg = CA_SUM/CA;
     TX_avg = TX_SUM/TX;
     AX_avg = AX_SUM/AX; 
     printf("CA Rainfall: %5.2f",CA_avg);
     printf("CA Rainfall: %5.2f",TX_avg);
     printf("CA Rainfall: %5.2f",AX_avg);
    }

I call the program using the command   awk 'FS="\t"'-f awk1.awk rainfall.txtand do not see the exit.

Question: Where am I slipping? Any suggestions and modified code will be appreciated

Answer 1

/ CA / {CA++; cA_SUM+= $5} # ^CA$ - Regular Expression to match the word CA only 
/ TX / {TX++; TX_SUM+= $5} # ^TX$ - Regular Expression to match the word TX only  
/ AX / {AX++; AX_SUM+= $5} # ^AX$ - Regular Expression to match the word AX only 

/^ AX $/

!

/ CA / {CA++; CA_SUM+= $5} # ^CA$ - Regular Expression to match the word CA only 
/ TX / {TX++; TX_SUM+= $5} # ^TX$ - Regular Expression to match the word TX only  
/ AX / {AX++; AX_SUM+= $5} # ^AX$ - Regular Expression to match the word AX only 
END {

 if(CA!=0){CA_avg = CA_SUM/CA;     printf("CA Rainfall: %5.2f",CA_avg);}
 if(TX!=0){TX_avg = TX_SUM/TX;     printf("TX Rainfall: %5.2f",TX_avg);}
 if(AX!=0){TX_avg = AX_SUM/CA;     printf("AX Rainfall: %5.2f",AX_avg);}
}

Answer 2

/^CA$/ , "C" "A" . :

$2 == "CA" {CA++; CA_SUM+= $5}
# etc.

DRYer:

{ count[$2]++; sum[$2] += $5 }
END {
    for (state in count) {
        printf("%s Rainfall: %5.2f\n", state, sum[state]/count[state])
    }
}

, : awk 'FS="\t"'-f awk1.awk rainfall.txt
: awk -F '\t' -f awk1.awk rainfall.txt

---

:

awk -F '\t' -v month=2 -v states="CA,AZ,TX" '
    BEGIN {
        month_col = month + 3  # assume January is month 1
        split(states, wanted_states, /,/)
    }
    { count[$2]++; sum[$2] += $month_col }
    END {
        for (state in wanted_states) {
            if (state in count) {
                printf("%s Rainfall: %5.2f\n", state, sum[state]/count[state])
            else
                print state " Rainfall: no data"
        }
    }
' rainfall.txt