null calculator

[esp]

I am getting an error after reading in a file ... File "C:\Users\patakye\Documents\EP_EDU\GradSchool\UMN\KiaResearch\QuantumSimulations\ATK\ATKSIMS\gnr_12_0_AGNR_z10.py", line 672, in doCalcs2     calculator(electrode_voltages=(-0.1*Volt,0.1*Volt)), TypeError: 'NoneType' object is not callable My setup is like this ... I create the device in one function and save it as:

Code

	#----------------------------------------
	# Device Calculator
	#----------------------------------------
	calculator = DeviceHuckelCalculator(
		basis_set=basis_set,
		electrode_voltages=(-0.1*Volt,0.1*Volt),
		electrode_calculators=
			[left_electrode_calculator, right_electrode_calculator],
		)

	device_configuration.setCalculator(calculator)
	nlprint(device_configuration)
	device_configuration.update()
	nlsave(outFileName, device_configuration)

then in another function:

Code

	#read in the old configuration
	device_configuration = nlread(outFileName,DeviceConfiguration)[0]
	calculator = device_configuration.calculator()

This is where I get an error that the calculator object is null ... am i doing this incorrectly?

[esp]

I think I figured this one out .. i saved multiple times and there were multiple device configurations in the file .. i used the object_id when saving and reading, and it works now. 

[Nordland]

You bet me to it.

When I had enter my answer it said newer post since last edit.

Good you found out.