app.py

import os
import csv
import random
import shutil
import pandas as pd
import gradio as gr

DATA_DIR = "./data"


def list_to_csv(list_of_dicts: list, filename: str):
    keys = dict(list_of_dicts[0]).keys()
    with open(filename, "w", newline="", encoding="utf-8") as csvfile:
        writer = csv.DictWriter(csvfile, fieldnames=keys)
        writer.writeheader()
        for data in list_of_dicts:
            writer.writerow(data)

    return filename


def random_allocation(participants: int, ratio: list):
    total = sum(ratio)
    splits = [0]
    for i, r in enumerate(ratio):
        splits.append(splits[i] + int(1.0 * r / total * participants))

    splits[-1] = participants
    partist = list(range(1, participants + 1))
    random.shuffle(partist)
    allocation = []
    groups = len(ratio)
    for i in range(groups):
        start = splits[i]
        end = splits[i + 1]
        for participant in partist[start:end]:
            allocation.append({"id": participant, "group": i + 1})

    sorted_data = sorted(allocation, key=lambda x: x["id"])
    filename = list_to_csv(sorted_data, f"{DATA_DIR}/output.csv")
    return filename, pd.DataFrame(sorted_data)


def infer(participants: float, ratios: str):
    if os.path.exists(DATA_DIR):
        shutil.rmtree(DATA_DIR)

    os.makedirs(DATA_DIR, exist_ok=True)
    ratio_list = ratios.split(":")
    ratio = []
    try:
        for r in ratio_list:
            current_ratio = float(r.strip())
            if current_ratio > 0:
                ratio.append(current_ratio)

    except Exception:
        print("Invalid input of ratio!")

    return random_allocation(int(participants), ratio)


if __name__ == "__main__":
    gr.Interface(
        fn=infer,
        inputs=[
            gr.Number(
                label="Number of participants",
                value=10,
            ),
            gr.Textbox(
                label="Grouping ratio",
                value="8:1:1",
                show_copy_button=True,
            ),
        ],
        outputs=[
            gr.File(label="Download data CSV"),
            gr.Dataframe(label="Data preview"),
        ],
        title="Randomized Controlled Trial Generator",
        description="Enter the number of participants and the grouping ratio in the format of numbers separated by : to generate randomized grouping data.",
        flagging_mode="never",
    ).launch()