Available with Spatial Analyst license.
Overview
Calculates the inverse tangent of the pixels in a raster.
Notes
In mathematics, all trigonometric functions have a defined range of valid input values, called the domain. The output values from each function also have a defined range. For this tool, the domain and range are as follows:
 Domain: ∞ < [in_value] < ∞
 Range: pi/2 ≤ [out_value] ≤ pi/2
The input values to this tool are interpreted as unitless.
The output raster is always a floatingpoint type, regardless of the input value type.
The output values from this tool are in radians. If degrees are desired, the resulting raster must be multiplied by the radianstodegrees conversion factor of 180/pi, or approximately 57.296.
For further assistance, a procedure to follow and some examples of converting output in radians to degrees are available.
Parameters
Parameter name  Description 

Raster  The input for which to calculate the inverse tangent values. 
Extent Type  Choose which extent should be used in the output raster:

Cellsize Type  Choose which cell size to use in the output raster. If all the input cell sizes are the same, all the options will yield the same results.
