Import a Calibration

Purpose of this Chapter

The aim of this chapter is to explain how you can create a calibration. This will be presented by taking a fictional example.

Overview

During a deployment, the efficiency of the instruments decreases, which also influences the data quality. Thus a pre-calibration and a post-calibration will be performed to analyze this effect. These calibrations will be used to create calibration functions that will be applied on the data to improve the data quality. These calibration functions have to be stored in the database to retrace the process chain. A calibration function has a function type and several calibration parameters that are required for calculations.

Create a Calibration

In this chapter, we will create a pre and post-calibration for the ICH unit. The database allows you to create calibrations for single components (e.g., PT100 sensor) or assembled components (e.g., ICH unit). Depending on the deployment, it will be determined if the calibration is a pre- or post-calibration. For example, suppose your instrument was deployed from 01.01.2020 to 01.01.2021. In that case, the calibration with the latest timestamp before 01.01.2020 is the pre-calibration, and the calibration with the earliest timestamp after 01.01.2021 is the post-calibration. If a calibration was performed over several days, it’s recommended to use the last timestamp and to create only one entry for it instead of creating an entry for each day.

Create Parameters

Via Python

First, we define the metadata in the dictionary METADATA. After it, we iterate over the dictionary and create database entries for the parameters. The created entries will be stored in the dictionary parameters for later purposes.

from IAGOS.apps.database.components import models as components

METADATA = {"A": "ppm", "B": "ppm"}
parameters = {}
for name in METADATA:
    unit = METADATA[name]
    parameters[name], _ = components.Parameter.objects.get_or_create(name=name, unit=unit)

Via Web Interface

Make sure that you have the permissions to create new entries (admin)
Go to the menu Components → Parameters
Create the parameters A (Unit: ppm) and B (Unit: ppm) by clicking the button create*

Create Calibrations

After we created the parameters, we will create metadata of the calibrations. Each calibration has to be assigned to a component and has a timestamp. Optional, you can set a name and a description for better identification.

Via Python

from datetime import datetime
from IAGOS.apps.database.components import models as components

pre_calibration, _ = components.Calibration.objects.get_or_create(
    component=instances["ICH"], name="Calibration X", timestamp=datetime(2019, 12, 24)
)
post_calibration, _ = components.Calibration.objects.get_or_create(
    component=instances["ICH"], name="Calibration Y", timestamp=datetime(2022, 1, 6)
)

Via Web Interface

Make sure that you have the permissions to create new entries (admin)
Go to the menu Components → Calibration
Create the calibrations Calibration X and Calibration Y by clicking the button on the top right.
- Name: Calibration X, Component: ICH, Timestamp: 2019-12-24
- Name: Calibration Y, Component: ICH, Timestamp: 2022-01-06

Assign Calibration Parameters

Each calibration parameter refers to the calibration and to the metadata of the parameter which we already created in the last sections. Based on it, we can create the calibration parameters. We create the two parameters A and B for the pre-calibration and two parameters for the post-calibration.

Via Python

from IAGOS.apps.database.components import models as components

pre_a, _ = components.CalibrationParameter.objects.get_or_create(
    parameter=parameters["A"], calibration=pre_calibration, value=42
)
post_a, _ = components.CalibrationParameter.objects.get_or_create(
    parameter=parameters["A"], calibration=post_calibration, value=40.5
)
pre_b, _ = components.CalibrationParameter.objects.get_or_create(
    parameter=parameters["B"], calibration=pre_calibration, value=666
)
post_b, _ = components.CalibrationParameter.objects.get_or_create(
    parameter=parameters["B"], calibration=post_calibration, value=642
)

Via Web Interface

Make sure that you have the permissions to create new entries (admin)
Go to the menu Components → Calibrations
Click on Details to see the detail view of the calibration.
Click on the button Parameter to assign a new parameter
Select the parameter and enter the value.

Create a Calibration Function

Important

The calibration functions can’t be handled via the web interface. You have to create them during the import process.

from IAGOS.apps.database.components import models as components

function_type, _ = components.FunctionType.objects.get_or_create(
    name="Linear interpolation"
)
function, _ = components.Function.objects.get_or_create(
    function_type=function_type, name="Function"
)
function.calibration_parameters.add(pre_a)
function.calibration_parameters.add(post_a)
function.save()