Problems with parameters creating a tool with python.

CarlosGutierrez

First of all thank you for anybody willing to help me.
I am trying to learn how to create a tool that will calculate the multiplication of 4 rasters. The code in python works and gives me an output raster but the tool I am trying to create does not. I am not sure if I am calling the rasters right with GetParameters. Please help I appreciate any comments on the code. Thank you
import arcpy


class Toolbox(object):
    def __init__(self):
        """Define the toolbox (the name of the toolbox is the name of the
        .pyt file)."""
        self.label = "Toolbox"
        self.alias = ""

        # List of tool classes associated with this toolbox
        self.tools = [Tool]


class Tool(object):
    def __init__(self):
        """Define the tool (tool name is the name of the class)."""
        self.label = "Tool"

    def getParameterInfo(self):
        """Define parameter definitions"""

# First parameter
        param0 = arcpy.Parameter(
        displayName="1",
        name="f1raster",
        datatype="DERasterDataset",
        parameterType="Required",
        direction="Input")

# Second parameter
        param1 = arcpy.Parameter(
        displayName="2",
        name="f2raster",
        datatype="DERasterDataset",
        parameterType="Required",
        direction="Input")

# Third parameter
        param2 = arcpy.Parameter(
        displayName="3",
        name="f3raster",
        datatype="DERasterDataset",
        parameterType="Required",
        direction="Input")

# Fouth parameter
        param3 = arcpy.Parameter(
        displayName="4",
        name="f4raster",
        datatype="DERasterDataset",
        parameterType="Required",
        direction="Input")

params = [param0, param1, param2, param3]

return params

    def isLicensed(self):
        """Set whether tool is licensed to execute."""
        return True

    def updateParameters(self, parameters):
        """Modify the values and properties of parameters before internal
        validation is performed.  This method is called whenever a parameter
        has been changed."""
        return

    def updateMessages(self, parameters):
        """Modify the messages created by internal validation for each tool
        parameter.  This method is called after internal validation."""
        return

    def execute(self, parameters, messages):
        """The source code of the tool."""
f1raster = arcpy.GetParameter(0)
f2raster = arcpy.GetParameter(1)
f3raster = arcpy.GetParameter(2)
f4raster = arcpy.GetParameter(3)
outraster = (f1raster * f2raster * f3raster * f4raster)
outraster.save("C:/REP/REP.tif")
        return

CarlosGutierrez

It works!!! Thanks Doug I appreciate your help with a newbee. I had tried getting the answer elsewhere but had no luck. You are awesome!