实战演练

• 普通算数

[root@shaofeng ~]# no1=4
[root@shaofeng ~]# no2=5

[root@shaofeng ~]# let no1+=5
[root@shaofeng ~]# echo $no1
9
[root@shaofeng ~]# result=$[ no1 + no2 ]
[root@shaofeng ~]# echo $result
14

• bc

  • 计算平方以及平方根

  [root@shaofeng ~]# echo "sqrt(100)" | bc
  10
  

• • 设定小数精度

  [root@shaofeng ~]# echo "scale=2;8/3" | bc
  2.66
  

  • 进制转换

  [root@shaofeng ~]# no=100
  [root@shaofeng ~]# echo "obase=2;$no" |bc
  1100100
  [root@shaofeng ~]# no=1100100
  [root@shaofeng ~]# echo "obase=10;ibase=2;$no" | bc
  100