diff --git a/Cargo.toml b/Cargo.toml
index 32ad5c4..3d0d767 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,4 @@ edition = "2021"
 
 [dependencies]
 meval = "0.2.0"
+image = "0.24.8"
diff --git a/grid_image.png b/grid_image.png
new file mode 100644
index 0000000..32e6587
Binary files /dev/null and b/grid_image.png differ
diff --git a/src/function.rs b/src/function.rs
new file mode 100644
index 0000000..7964f4b
--- /dev/null
+++ b/src/function.rs
@@ -0,0 +1,149 @@
+pub fn default_points(points: &mut [[f64;2];3]) {
+    if points.iter().all(|row| row.iter().all(|&x| x == 0.0)) {
+        *points = [[-1.0,1.0], [2.0,4.0], [3.0,9.0]];
+    }
+}
+
+pub fn group_by_x(arr: &mut [[f64;2];3]) {
+    arr.sort_by(|a, b| a[0].partial_cmp(&b[0]).unwrap_or(std::cmp::Ordering::Equal));
+}
+
+pub fn get_points(args: Vec<String>) -> [[f64;2];3] {
+    let mut points: [[f64; 2]; 3] = [[0.0; 2]; 3];
+
+    for (i, part) in args.iter().enumerate().take(3) {
+        let values: Vec<f64> = part
+            .split(':')
+            .filter_map(|s| s.parse().ok())
+            .collect();
+
+        if values.len() == 2 {
+            points[i][0] = values[0];
+            points[i][1] = values[1];
+        } else {
+            println!("Invalid input format: {}", part);
+            println!("Usage: $0 -1:1 3:-5 10:1.5")
+        }
+    }
+
+    #[cfg(debug_assertions)]
+    default_points(&mut points);
+
+    points
+}
+
+fn nearest_to_zero(arr: &[[f64;2];3]) -> usize {
+    let mut nearest = arr[1][1];
+    let mut nearest_index = 0;
+    for (i, point) in arr.iter().enumerate() {
+        if nearest < point[1].abs() {
+            nearest = point[i-1];
+            nearest_index = i-1;
+        }
+    }
+    nearest_index
+}
+
+pub fn straight_string(m: f64, points: &[[f64;2];3]) -> String {
+    format!(
+        "{}x{}",
+        if m != 1.0 {
+            format!("{} * ", m)
+        } else {
+            "".to_string()
+        },
+        {
+            let lowest_y = nearest_to_zero(points);
+            let result = points[lowest_y][0] - points[lowest_y][1] * m;
+            if result != 0.0 {
+                format!(
+                    "{}{}",
+                    if result < 0.0 {
+                        " - ".to_string()
+                    } else {
+                        " + ".to_string()
+                    },
+                    result.abs()
+                )
+            } else {
+                "".to_string()
+            }
+        }
+    )
+}
+
+pub fn square_string(points: &[[f64;2];3]) -> String {
+    let a = -((points[0][0] * points[1][1] - 
+            points[0][0] * points[2][1] -
+            points[1][0] * points[0][1] +
+            points[1][0] * points[2][1] +
+            points[2][0] * points[0][1] -
+            points[2][0] * points[1][1])
+            /
+            ((points[0][0] - points[1][0]) *
+            (points[0][0] - points[2][0]) *
+            (points[1][0] - points[2][0])));
+
+    let b = (points[0][0].powi(2) * points[1][1] -
+            points[0][0].powi(2) * points[2][1] -
+            points[1][0].powi(2) * points[0][1] +
+            points[1][0].powi(2) * points[2][1] +
+            points[2][0].powi(2) * points[0][1] -
+            points[2][0].powi(2) * points[1][1])
+            /
+            ((points[0][0] - points[1][0]) *
+            (points[0][0] - points[2][0]) *
+            (points[1][0] - points[2][0]));
+
+    let c = (points[0][0].powi(2) * points[1][0] * points[2][1] -
+            points[0][0].powi(2) * points[2][0] * points[1][1] -
+            points[0][0] * points[1][0].powi(2) * points[2][1] +
+            points[0][0] * points[2][0].powi(2) * points[1][1] +
+            points[1][0].powi(2) * points[2][0] * points[0][1] -
+            points[1][0] * points[2][0].powi(2) * points[0][1])
+            /
+            ((points[0][0] - points[1][0]) *
+            (points[0][0] - points[2][0]) *
+            (points[1][0] - points[2][0]));
+
+    format!(
+        "{}x^2{}{}",
+        if a == -1.0 {
+            "-".to_string()
+        } else if a != 1.0 {
+            format!("{}{}", a, " * ")
+        } else {
+            "".to_string()
+        },
+        if b != 0.0 {
+            format!(
+                "{}{}",
+                if b < 0.0 {
+                    " - ".to_string()
+                } else {
+                    " + ".to_string()
+                },
+                if b != 1.0 {
+                    format!("{} * x", b.abs())
+                } else {
+                    "x".to_string()
+                }
+            )
+        } else {
+            "".to_string()
+        },
+        if c != 0.0 {
+            format!(
+                "{}{}",
+                if c < 0.0 {
+                    " - ".to_string()
+                } else {
+                    " + ".to_string()
+                },
+                c.abs()
+            )
+        } else {
+            "".to_string()
+        }
+    )
+}
diff --git a/src/image.rs b/src/image.rs
new file mode 100644
index 0000000..0c8e285
--- /dev/null
+++ b/src/image.rs
@@ -0,0 +1,21 @@
+use image::{ImageBuffer, RgbImage, Rgb}; 
+
+pub fn get_image(width: u32, height: u32) -> ImageBuffer<Rgb<u8>, Vec<u8>> {
+    let mut img = RgbImage::new(width, height);
+    let grid_spacing = 100;
+    let grid_color = Rgb([255,9,255]);
+
+    for x in (0..width).step_by(grid_spacing) {
+        for y in 0..height {
+            img.put_pixel(x, y, grid_color);
+        }
+    }
+    for y in (0..height).step_by(grid_spacing) {
+        for x in 0..width {
+            img.put_pixel(x, y, grid_color);
+        }
+    }
+    img
+}
+
+
diff --git a/src/main.rs b/src/main.rs
index 6ec17c8..2334a6c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,27 +1,13 @@
 use std::env;
 
+mod function;
+mod image;
+use crate::function::*;
+
 fn main() {
     let args: Vec<String> = env::args().skip(1).take(3).collect();
-    let mut points: [[f64; 2]; 3] = [[0.0; 2]; 3];
-
-    for (i, part) in args.iter().enumerate().take(3) {
-        let values: Vec<f64> = part
-            .split(':')
-            .filter_map(|s| s.parse().ok())
-            .collect();
-
-        if values.len() == 2 {
-            points[i][0] = values[0];
-            points[i][1] = values[1];
-        } else {
-            println!("Invalid input format: {}", part);
-            println!("Usage: $0 -1:1 3:-5 10:1.5")
-        }
-    }
-
-    #[cfg(debug_assertions)]
-    default_points(&mut points);
 
+    let mut points = get_points(args);
     group_by_x(&mut points);
 
     let m1 = (points[0][1] - points[1][1]) / (points[0][0] - points[1][0]);
@@ -34,135 +20,53 @@ fn main() {
     if function.contains("NaN") {
         panic!("Contains NaN, this is probably the result of bad math");
     }
-    // let expr2 = tokenize(function.as_str()).unwrap();
-    // println!("{:?}", expr2);
+
     let rust_function = function.parse::<meval::Expr>().unwrap().bind("x").unwrap();
     let result = rust_function(9.0);
     println!("{}", result);
-}
 
-fn default_points(points: &mut [[f64;2];3]) {
-    if points.iter().all(|row| row.iter().all(|&x| x == 0.0)) {
-        *points = [[-1.0,1.0], [2.0,4.0], [3.0,9.0]];
+    /*
+    let width = 7000;
+    let height = 7000;
+    let color = [255, 0, 0];
+    let mut img = get_image(4000, 4000);
+    let step: f64 = format!("0.{}1", "0".repeat(6)).parse().unwrap();
+    let mut points = vec![];
+
+    let mut i = 0.0;
+    while i <= 3.0 {
+        points.push(i);
+        i += step;
     }
-}
 
-fn group_by_x(arr: &mut [[f64;2];3]) {
-    arr.sort_by(|a, b| a[0].partial_cmp(&b[0]).unwrap_or(std::cmp::Ordering::Equal));
-}
 
-fn nearest_to_zero(arr: &[[f64;2];3]) -> usize {
-    let mut nearest = arr[1][1];
-    let mut nearest_index = 0;
-    for (i, point) in arr.iter().enumerate() {
-        if nearest < point[1].abs() {
-            nearest = point[i-1];
-            nearest_index = i-1;
+    // println!("{points:?}");
+
+
+    let mut x;
+    let mut y;
+    // let mut x_result_tmp;
+    // let mut y_result_tmp;
+    for point in points {
+        // NOTE: convert later to u32 because deviding may change actual value
+        x = point * 1000.0_f64;
+        y = rust_function(point) * 1000.0;
+        if width as f64 / 2.0 + y < (width - 5) as f64 {
+            img.put_pixel(
+                (width as f64 / 2.0 + x).round() as u32,
+                (height as f64 / 2.0 - y) as u32,
+                Rgb(color)
+            );
+            img.put_pixel(
+                (width as f64 / 2.0 - x).round() as u32,
+                (height as f64 / 2.0 - y).round() as u32,
+                Rgb(color)
+            );
         }
     }
-    nearest_index
+
+    img.save("grid_image.png").expect("Failed to save image");
+    */
 }
 
-fn straight_string(m: f64, points: &[[f64;2];3]) -> String {
-    format!(
-        "{}x{}",
-        if m != 1.0 {
-            format!("{} * ", m)
-        } else {
-            "".to_string()
-        },
-        {
-            let lowest_y = nearest_to_zero(points);
-            let result = points[lowest_y][0] - points[lowest_y][1] * m;
-            if result != 0.0 {
-                format!(
-                    "{}{}",
-                    if result < 0.0 {
-                        " - ".to_string()
-                    } else {
-                        " + ".to_string()
-                    },
-                    result.abs()
-                )
-            } else {
-                "".to_string()
-            }
-        }
-    )
-}
 
-fn square_string(points: &[[f64;2];3]) -> String {
-    let a = -((points[0][0] * points[1][1] - 
-            points[0][0] * points[2][1] -
-            points[1][0] * points[0][1] +
-            points[1][0] * points[2][1] +
-            points[2][0] * points[0][1] -
-            points[2][0] * points[1][1])
-            /
-            ((points[0][0] - points[1][0]) *
-            (points[0][0] - points[2][0]) *
-            (points[1][0] - points[2][0])));
-
-    let b = (points[0][0].powi(2) * points[1][1] -
-            points[0][0].powi(2) * points[2][1] -
-            points[1][0].powi(2) * points[0][1] +
-            points[1][0].powi(2) * points[2][1] +
-            points[2][0].powi(2) * points[0][1] -
-            points[2][0].powi(2) * points[1][1])
-            /
-            ((points[0][0] - points[1][0]) *
-            (points[0][0] - points[2][0]) *
-            (points[1][0] - points[2][0]));
-
-    let c = (points[0][0].powi(2) * points[1][0] * points[2][1] -
-            points[0][0].powi(2) * points[2][0] * points[1][1] -
-            points[0][0] * points[1][0].powi(2) * points[2][1] +
-            points[0][0] * points[2][0].powi(2) * points[1][1] +
-            points[1][0].powi(2) * points[2][0] * points[0][1] -
-            points[1][0] * points[2][0].powi(2) * points[0][1])
-            /
-            ((points[0][0] - points[1][0]) *
-            (points[0][0] - points[2][0]) *
-            (points[1][0] - points[2][0]));
-
-    format!(
-        "{}x^2{}{}",
-        if a == -1.0 {
-            "-".to_string()
-        } else if a != 1.0 {
-            format!("{}{}", a, " * ")
-        } else {
-            "".to_string()
-        },
-        if b != 0.0 {
-            format!(
-                "{}{}",
-                if b < 0.0 {
-                    " - ".to_string()
-                } else {
-                    " + ".to_string()
-                },
-                if b != 1.0 {
-                    format!("{} * x", b.abs())
-                } else {
-                    "x".to_string()
-                }
-            )
-        } else {
-            "".to_string()
-        },
-        if c != 0.0 {
-            format!(
-                "{}{}",
-                if c < 0.0 {
-                    " - ".to_string()
-                } else {
-                    " + ".to_string()
-                },
-                c.abs()
-            )
-        } else {
-            "".to_string()
-        }
-    )
-}