How could I define a quantiy for instance current by reading input values in file?

In order to define a quantity (for instance current), by reading input values in file, you have to follow the next steps:

1	Create a txt file with input values. Example: The file I_1.txt that contains values of time and corresponding current values: 0 0 0.1 1.1 0.2 1.5
2	Create new I/O parameter by importation of a 2D table. From menu Parameter/Quantity i/O parameter New tablulated I/O parameter by importation of a 2D table
3	Use the created I/O parameter to define a quantity, for instance you can use I_1 as formula defining the current source in the circuit.

Create a txt file with input values.
Example: The file I_1.txt that contains values of time and corresponding current values:
0 0
0.1 1.1
0.2 1.5

Create new I/O parameter by importation of a 2D table.
From menu Parameter/Quantity i/O parameter New tablulated I/O parameter by importation of a 2D table

Use the created I/O parameter to define a quantity, for instance you can use I_1 as formula defining the current source in the circuit.