Do calculation in linux

calculator bash script

The recommended way to evaluate arithmetic expressions with integers in Bash is to use the Arithmetic Expansion capability of the shell. The builtin shell expansion allows you to use the parentheses ((. )) to do math calculations. The format for the Bash arithmetic expansion is $(( arithmetic expression )) .

Does shell script do calculations?

However, it is possible to do math with shell script.
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Arithmetic Operators.

+ —	Addition, subtration
++ —	Increment, decrement
* / %	Multiplication, division, remainder
**	Exponentiation

How do I make a calculator in terminal?

To open it, simply type calc in a terminal and hit Enter. Like bc, you’ll need to use typical operators. For example, 5 * 5 for five multiplied by five. When you type a calculation, hit Enter.

What is BC in bash script?

BC, which stands for Basic Calculator, is a command in Bash that is used to provide the functionality of a scientific calculator within a Bash script. This can be useful for scripting with various arithmentic use cases and scenarios.

How do I run a shell script?

1. Open the terminal. Go to the directory where you want to create your script.
2. Create a file with . sh extension.
3. Write the script in the file using an editor.
4. Make the script executable with command chmod +x .
5. Run the script using ./.

How do you calculate in Linux?

1. Plus : Addition.
2. Minus : Subtraction.
3. Forward Slash : Division.
4. Asterisk: Used for Multiplication.

How do I find float value in Linux?

1. use the shell debugging/trace options ( set -vx ) to see what values are being processed, then you can adjust your string parsing to just retrieve the number parts. .
2. Same question on Unix & Linux: Perform floating point arithmetic in shell script variable definitions – Palec Feb 10 ’15 at 22:53.

How do you do arithmetic operations in bash?

The oldest command for doing arithmetic operations in bash is ‘expr’. This command can work with integer values only and prints the output directly in the terminal. You have to use space with each operand when you want to use ‘expr’ command to do any mathematical operations.

Does Linux do math?

The expr or the expression command in Linux is the most commonly used command that is used to perform mathematical calculations. You can use this command to perform functions like addition, subtraction, multiplication, division, incrementing a value and, even comparing two values.

How do I sum a shell script?

num1=1232 num2=24 num3=444 . . . let SUM=$num1+num2+num3.

How do you calculate in Unix?

1. Using Bash Shell. The first and easiest way do basic math on the Linux CLI is a using double parenthesis. .
2. Using expr Command. The expr command evaluates expressions and prints the value of provided expression to standard output. .
3. Using bc Command. .
4. Using Awk Command. .
5. Using factor Command.

Install

Please follow our steps below to install and configure ELK stack tools on CentOS 7 / Fedora 31/30/29 Linux.Step 1: Install Java. . Step 2: Add ELK r.

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5 Useful Ways to Do Arithmetic in Linux Terminal

In this article, we will show you various useful ways of doing arithmetic’s in the Linux terminal. By the end of this article, you will learn basic different practical ways of doing mathematical calculations in the command line.

1. Using Bash Shell

The first and easiest way do basic math on the Linux CLI is a using double parenthesis. Here are some examples where we use values stored in variables:

$ ADD=$(( 1 + 2 )) $ echo $ADD $ MUL=$(( $ADD * 5 )) $ echo $MUL $ SUB=$(( $MUL - 5 )) $ echo $SUB $ DIV=$(( $SUB / 2 )) $ echo $DIV $ MOD=$(( $DIV % 2 )) $ echo $MOD

2. Using expr Command

The expr command evaluates expressions and prints the value of provided expression to standard output. We will look at different ways of using expr for doing simple math, making comparison, incrementing the value of a variable and finding the length of a string.

The following are some examples of doing simple calculations using the expr command. Note that many operators need to be escaped or quoted for shells, for instance the * operator (we will look at more under comparison of expressions).

$ expr 3 + 5 $ expr 15 % 3 $ expr 5 \* 3 $ expr 5 – 3 $ expr 20 / 4

Next, we will cover how to make comparisons. When an expression evaluates to false, expr will print a value of 0, otherwise it prints 1.

Let’s look at some examples:

$ expr 5 = 3 $ expr 5 = 5 $ expr 8 != 5 $ expr 8 \> 5 $ expr 8 \< 5 $ expr 8 \

You can also use the expr command to increment the value of a variable. Take a look at the following example (in the same way, you can also decrease the value of a variable).
$ NUM=$(( 1 + 2)) $ echo $NUM $ NUM=$(expr $NUM + 2) $ echo $NUM
 
 
Let’s also look at how to find the length of a string using:
 
$ expr length "This is Tecmint.com"
 
 
For more information especially on the meaning of the above operators, see the expr man page:
 
3. Using bc Command
 
bc (Basic Calculator) is a command-line utility that provides all features you expect from a simple scientific or financial calculator. It is specifically useful for doing floating point math.
 
If bc command not installed, you can install it using:
 
$ sudo apt install bc #Debian/Ubuntu $ sudo yum install bc #RHEL/CentOS $ sudo dnf install bc #Fedora 22+
 
Once installed, you can run it in interactive mode or non-interactively by passing arguments to it – we will look at both case. To run it interactively, type the command bc on command prompt and start doing some math, as shown.
 
 
The following examples show how to use bc non-interactively on the command-line.
 
$ echo '3+5' | bc $ echo '15 % 2' | bc $ echo '15 / 2' | bc $ echo '(6 * 2) - 5' | bc
 
 
The -l flag is used to the default scale (digits after the decimal point) to 20, for example:
 
$ echo '12/5 | bc' $ echo '12/5 | bc -l'
 
 
4. Using Awk Command
 
Awk is one of the most prominent text-processing programs in GNU/Linux. It supports the addition, subtraction, multiplication, division, and modulus arithmetic operators. It is also useful for doing floating point math.
 
You can use it to do basic math as shown.
 
$ awk 'BEGIN < a = 6; b = 2; print "(a + b) = ", (a + b) >' $ awk 'BEGIN < a = 6; b = 2; print "(a - b) = ", (a - b) >' $ awk 'BEGIN < a = 6; b = 2; print "(a * b) = ", (a * b) >' $ awk 'BEGIN < a = 6; b = 2; print "(a / b) = ", (a / b) >' $ awk 'BEGIN < a = 6; b = 2; print "(a % b) attachment_31503" aria-describedby="caption-attachment-31503" style="width: 822px" > 
If you are new to Awk, we have a complete series of guides to get you started with learning it: Learn Awk Text Processing Tool.
 
5. Using factor Command
 
The factor command is use to decompose an integer into prime factors. For example:
 
$ factor 10 $ factor 127 $ factor 222 $ factor 110
 
 
That’s all! In this article, we have explained various useful ways of doing arithmetic’s in the Linux terminal. Feel free to ask any questions or share any thoughts about this article via the feedback form below.
 
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