What is the ATAN function in Excel?
The ATAN function is one of the math functions of Excel. It returns the arctangent of a number in radians, in the range Of -pi/2 to Pi/2.
We can find this function in the Math&trig section of the insert function Tab.
How to use ATAN function in excel
- Click on an empty cell (like F5 )

2. Click on the fx icon (or press shift+F3)

3. In the insert function tab you will see all functions

4. Select math and trig category
5. Select the ATAN function
6. Then select ok

7. In the function arguments Tab you will see the ATAN function
8. In the Number section you can enter the tangent of the angle you want
9. You will see the result in the formula result section ( ATAN (0)=0)

Examples of ATAN function in excel
Example 1:
How to use ATAN function in excel
You can see examples of ATAN function below:

atan(-1) ----->>>>answer is -0.785
atan(-0.5) ----->>>>answer is -0.463
atan(0) ----->>>>answer is 0
atan(0.5) ----->>>>answer is 0.463
atan(1) ----->>>>answer is 0.785
math.atan(a)
How to plot Y=ATAN(X) with python code in excel
import math
import numpy as np
import matplotlib.pyplot as plt
x =np.linspace(–2,+2, 100)
lenx=len(x)
y=[]
for i in range(lenx):
y.append(math.atan(x[i]))
i +=1
plt.plot(x,y)
plt.show()
What is the purpose of ATAN function?
It returns the arctangent of a number in radians, in the range Of -pi/2 to Pi/2.
What is the Return value of ATAN function?
It returns a number.
How many arguments does ATAN function have?
This function has just 1 Argument.
The argument of ATAN function is number.
In the Number section you can enter the tangent of the angle you want
The argument of ATAN function is required and not optional.
ATAN(number) = number
Which version of excel supports ATAN function?
This function is available for all excel versions (2003-2019)