Create Dataframe from unknown number of Series pandas

Question

I have a list of (user defined) objects known as "Instrument Measurements". These, have a title, accessible by Instrument_Measurement.name and a series of data accessible by Instrument_Measurement.data (both user defined methods).

These "Instrument Measurement" objects are items in a list called list_instr_objects. The number of items ("Instrument Measurements") changes/cannot be hard-coded.

I need to create a Dataframe with column titles Instrument_Measurement.name for each "Instrument Measurement" and data for that column of Instrument_Measurement.data for that respective "Instrument Measurement".

I'm trying to do this by creating a dictionary of these objects and then converting that to a Dataframe:

from collections import defaultdict
testdict = defaultdict(list)

for i in range(len(list_instr_objects)):
    testdict[list_instr_objects[i].name].append(list_instr_objects[i].data)

This doesn't work though, only the first data entry for each instrument is kept and the entries come out in a seemingly random order. I think this is because I'm passing a Series to the dictionary where I should be passing a list, but I can't think how else to do it/how to fix this.

Any thoughts?

Many thanks in advance.

Answer 1

I think you can use OrderedDict to keep the order and use below code to generate the dataframe.

import pandas as pd
from collections import OrderedDict

testdict = OrderedDict()

for i in range(len(list_instr_objects)):
    testdict[list_instr_objects[i].name] = (list_instr_objects[i].data)

combined_data = pd.DataFrame(testdict)