Set projection from user input with Arcpy

Question

This seems like to should be an easy thing to do, but I can't seem to make it work.

arcpy.env.workspace = arcpy.GetParameterAsText(0) 
output_working = arcpy.GetParameterAsText(1) 
PLSS_Intersected = arcpy.GetParameterAsText(2) 
spatial_ref = arcpy.GetParameterAsText(3) 
outCS = arcpy.SpatialReference("spatial_ref") 
outfc = os.path.join(output_working, "PLSS_Intersected") 
arcpy.Project_management(PLSS_Intersected, outfc, outCS) 

EDIT:

How is the error massage that I receive. The very top is what prints out when I printed outCS.enter image description here

• phloem: "spatial_ref" is a string, but spatial_ref is a variable holding a string.
• GeoSharp: One issue is you are providing the string 'spatial_ref' to arcpy.SpatialReference rather than the value you have assigned to spatial_ref via arcpy.GetParameterAsText(3)
• sd1272: How do I correct this? Rather, how do I call the value instead of calling the variable holding the value?
• GeoSharp: outCS = arcpy.SpatialReference(spatial_ref). This uses the variable, not a string that happens to be the variable name.
• PolyGeo: I think it will be worth using print outCS after you get that 4th parameter as text so that you (and we) can see what a test value is that you enter.

Answer 1

Although the comments have identified the immediate problem (that you are using the string literal, "spatial_ref", rather than the variable, spatial_ref), you may find it easier to change the input parameter to data type = Spatial Reference, and use the spatial reference object itself, rather than converting the spatial reference to string and back to a spatial reference object.

arcpy.env.workspace = arcpy.GetParameterAsText(0) 
output_working = arcpy.GetParameterAsText(1) 
PLSS_Intersected = arcpy.GetParameterAsText(2) 
spatial_ref = arcpy.GetParameter(3) # get spatial reference object
outfc = os.path.join(output_working, "PLSS_Intersected") 
arcpy.Project_management(PLSS_Intersected, outfc, spatial_ref) # set spatial reference to the object