經常使用命令--awk

awk '{ 
     BEGIN{stat1} 
     BEGIN{stat2} 
     pattern1{action1} 
     pattern2{action2} 
     ... 
     patternn{actionn} 
     {默認動做,無條件,始終執行} 
     END{stat1} 
     END{stat2} 
}'

awk 'BEGIN{
for(i=1;i<=9;i++)
    {
        for(j=1;j<=9;j++)  
        {
            tarr[i,j]=i*j;
            print i,"*",j,"=",tarr[i,j];
        }
    }
}'

# awk 打印 99乘法表 
awk 'BEGIN{
for(i=1;i<10;i++) 
    {
        for(j=1;j<=i;j++) 
        {
            printf "%d%s%d%s%d\t",j,"*",i,"=",i*j;
        }
        printf "\n"
    }
}'

# awk 浮點計算
aa=20645323448563562456
bb=1024532542341354
awk -v m1=$aa -v m2=$bb 'BEGIN{
    num = m1/m2;
    print m1;
    print m2;
    print num;
    printf "%.9f\n", num;
}'

# 計算器
firstNum=20645
secondNum=102.4
ss=`awk -v m1=$firstNum -v m2=$secondNum 'BEGIN{num = m1/m2; printf "%.9f\n", num;}'`
echo $ss
201.611328125