Storing data in CSV file using python

Hello!
I would like to read data from resistive sensor and store it in CSV file but i do not see the chage in CSV file when the value is changes.

please suggest me a solution.

int analogPin= 0;
int raw= 0;
int Vin= 3;
float Vout= 0;
float R1= 470000;
float R2= 0;
float buffer= 0;

void setup()
{
Serial.begin(9600);
}

void loop()
{
raw= analogRead(analogPin);
if(raw)
{
buffer= raw * Vin;
Vout= (buffer)/1024.0;
R2 = (Vout*R1)/(Vin-Vout);

Serial.print("Vout: ");
Serial.print(Vout);
Serial.print("V");
Serial.print(" ");
Serial.print("R2: ");
Serial.print(R2);
Serial.println("ohm");
delay(100);
}
}

import serial
import time
import csv
import matplotlib
arduino_port = "COM7"
baud = 115200
ser = serial.Serial(arduino_port, baud)
fileName="analog-data.csv"
file = open(fileName, "w")
print("Created file")
time.sleep(2)
ser.flushInput()

samples = int(input("How many sample you want ? :_ "))
line = 0
while line <= samples:
getData = str(ser.readline().decode())
data = getData[18:][:-5]
print(getData)
file = open(fileName, "a")
file.write(data+'\n')
line = line + 1

print("Data collection complete!")
file.close()

Is that a Python program ?

Yes

Then why are you asking for help on an Arduino forum when the Arduino is programmed in C++ ?

raw = analogRead(analogPin);
if (raw) {

This isn’t really helping much…
raw is almost guaranteed to be true ‘all the time’

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