bc:
it is used to operate all the operators
Description:
The
bc command evaluates all the operators in c .
-
Arithmetic
operators
-
Increment
and decrement operators
-
Assignment
operators
-
Relational
Operators
-
Logical
operators
-
Conditional
statements
-
Iterative
statements
1.Arithmetic
operator Examples:
1.
Finding Sum of Two expressions
>
echo "2+5" | bc
7
2.
Difference of Two numbers
>
echo "10-4" | bc
6
3.
Multiplying two numbers
>
echo "3*8" | bc
24
4.
Dividing two numbers
>
echo "2/3" | bc
0
>
echo "5/4" | bc
1
Use
the scale function to specify the number of decimal digits that the
bc command should return.
>
echo "scale=2;2/3" | bc
.66
5.
Finding the remainder using modulus operator
>
echo "6%4" | bc
2
6.
Using exponent operator
>
echo "10^2" | bc
100
Here
the expression is evaluated as 10 to the power of 2.
2.Increment
Operator Examples:
There
are two kinds of increment operators. They are pre increment and post
increment operators.
++var
: Pre increment operator. The variable is incremented first and then
the result of the variable is used.
var++
: Post increment operator. The result of the variable is used first
and then the variable is incremented.
>
echo "var=5;++var" | bc
6
>
echo "var=5;var++" | bc
5
Here,
in the second example the value of var is printed first and then it
is incremented. See the below example, to see the complete
incremental effect.
>
echo "var=5;var++;var" | bc
5
Decrement
Operator Examples:
Similar
to the increment operators, there are two types of decrement
operators.
--var
: Pre decrement operator. The variable is decremented first and then
the result of the variable is used.
var--
: Post decrement operator. The result of the variable is used first
and then the variable is decremented.
>
echo "var=5;--var"| bc
4
>
echo "var=5;var--"| bc
5
3.Assignment
Operator Examples:
Assigns
10 to the variable and prints the value on the terminal.
>
echo "var=10;var" | bc
Increment
the value of the variable by 5
>
echo "var=10; var+=5;var | bc
15
The
lists of assignment operators supported are:
var
= value : Assign the value to the variable
var
+= value : similar to var = var + value
var
-= value : similar to var = var - value
var
*= value : similar to var = var * value
var
/= value : similar to var = var / value
var
^= value : similar to var = var ^ value
var
%= value : similar to var = var % value
4.Relational
Operators Examples:
Relational
operators are used to compare two numbers. If the comparison is true,
then it returns 1. Otherwise (false), it returns 0.
expr1
< expr2 : Result is 1 if expr1 is strictly less than expr2.
expr1
<= expr2 : Result is 1 if expr1 is less than or equal to expr2.
expr1
> expr2 : Result is 1 if expr1 is strictly greater than expr2.
expr1
>= expr2 : Result is 1 if expr1 is greater than or equal to expr2.
expr1
== expr2 : Result is 1 if expr1 is equal to expr2.
expr1
!= expr2 : Result is 1 if expr1 is not equal to expr2.
Examples:
>
echo "10 > 5" | bc
1
>
echo "1 == 2" | bc
0
5.Logical
Operator Examples:
Logical
operators are also mostly used in conditional statements. The result
of the logical operators is either 1 (True) or 0 (false) ! expr :
Result is 1 if expr is 0.
expr
&& expr : Result is 1 if both expressions are non-zero.
expr
|| expr : Result is 1 if either expression is non-zero.
>
echo "4 && 10" | bc
1
>
echo "0 || 0" | bc
0
Examples:
The
syntax of if statement is
if(condition)
{
Statements
}
else
{
Statements
}
The
following example shows show to use the if condition
>
echo 'if(1 == 2) print "true" else print "false"'
| bc
false
Bc
command supports the for and while loop for doing iterations. The
syntax of for and while loop are shown below:
for
(assignment; condition; increment)
{
statements
}
while
(condition)
{
statements
}
The
following examples prints numbers from 1 to 10 using the for and
while loops
>
echo "for(i=1;i<=10;i++) {i;}" | bc
>
echo "i=1; while(i<=10) { i; i+=1}" | bc
