Calculator for Dataframes
I have solved the issue. For anybody who will need similar functions i report here the solution in steps

Write your equation with the name of your files. E.g. current_1 * voltage_1 (you need file current_1.csv, voltage_1.csv)

parse your equation with any parser. I used py_expression_eval.

Extract the variables from the equation (variables = parser.parse(equation).variables())

iterate over the variables and at each step:

load the data in a dataframe
insert the column of the measurement in general dataframe
change the name of that column to the name of your file (e.g. current_1)

by doing this you will obtain a dataframe with columns: time, measurement_1, measurement_2 ecc.

Use df.eval('result= ' + expression, inplace=True) to evaluate your initial expression using the columns you have added to the general dataframe


Hope this helps somebody
I want to make a calculator for my data.
Basically I have multiple measurements in different .csv files that are named as their physical representation (temperature_1, current_1, voltage_1 ecc.) and I am trying to make a calculator in python that given a certain expression [e.g. (current_1 * voltage_1) + (current_2 * voltage_2)] is able to load the data from each file and evaluates the result of the expression on the dataframes.
I already made simple functions in order to sum, subtract, multiply and divide dataframes but I am stuck on how to handle complex expressions like the sum of many multiplications [e.g. (current_1 * voltage_1) + (current_2 * voltage_2) + (current_3 * voltage_3) ecc.].
I tried to use a parser but still got no result.
Somebody has any idea on how to handle this?
Note: all the .csv have 2 columns, time and measurement, the number of rows are the same and the acquisition time is at the same timestamp.