#!/bin/bash
############################
#重寫shell中基本數學運算+ - × /
#時間:2014-01-18
#郵箱：[email protected]
#版本: version 1.0
#備注：目前只支持2位整數運算
############################
#####################
#function is_Digit()
#判斷參數是否為數字
#支持浮點數
#只能傳入一個參數
#是，返回1，否則返回0
######################
functionis_Digit()
{
ref=`echo$1 |  awk'{print($0~/^[+-]?[0-9]?*(/.[0-9]*)?$/)?"digit":"string"}'`
if[ "$ref"== "digit"];then
return0;
else
return1;
fi
}
###################
#function multiply()
#判斷參數是否為數字
#并將兩個參數相乘
#函數直接傳入引用
#變量的變量的實現${!para}
#函數的返回值，不能像C一樣return，
#需要打印輸出，echo
###################
functionmul()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%d /n",num_a*num_b}'`;
echo$ref;
}
########################
#function div()
#檢查參數，返回兩個數字差
########################
functiondiv()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%d /n",num_a/num_b}'`;
echo$ref;
}
########################
#function add()
#檢查參數，返回兩個數字和
########################
functionadd()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%d /n",num_a+num_b}'`;
echo$ref;
}
########################
#function sub()
#檢查參數，返回兩個數字差
########################
functionsub()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%d /n",num_a-num_b}'`;
echo$ref;
}
###################
#function mul_f()
#判斷參數是否為數字
#并將兩個參數相乘
#函數直接傳入引用
#變量的變量的實現${!para}
#函數的返回值，不能像C一樣return，
#需要打印輸出，echo
###################
functionmul_f()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%0.2f /n",num_a*num_b}'`;
echo$ref;
}
########################
#function div_f()
#檢查參數，返回兩個數字差
########################
functiondiv_f()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%0.2f /n",num_a/num_b}'`;
echo$ref;
}
########################
#function add_f()
#檢查參數，返回兩個數字和
########################
functionadd_f()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%0.2f /n",num_a+num_b}'`;
echo$ref;
}
########################
#function sub_f()
#檢查參數，返回兩個數字差
########################
functionsub_f()
{
for(( i=1;i<3;i++ ))
do
pa="$i"
ifis_Digit ${!pa}
then
continue;
else
echo"$pa isn't a number";
return0;
fi
done
ref=`awk-vnum_a=$1 -vnum_b=$2 'BEGIN{printf "%0.2f /n",num_a-num_b}'`;
echo$ref;
}