TEST: Plot results in test_pkg_lnn.py

Author: ubaidsk

integration_tests/test_pkg_lnn.py

@@ -1,5 +1,53 @@
 from lnn.perceptron import init_perceptron, print_perceptron, normalize_input_vectors, Perceptron, train_dataset
-from lpython import i32, f64
+from lpdraw import Line, Circle, Display, Clear
+from lpython import i32, f64, Const
+from numpy import empty, int32
+
+
+def compute_decision_boundary(p: Perceptron, x: f64) -> f64:
+    bias: f64 = p.weights[-1]
+    slope: f64 = (-p.weights[0] / p.weights[1])
+    intercept: f64 = (-bias / p.weights[1])
+    return slope * x + intercept
+
+def plot_graph(p: Perceptron, input_vectors: list[list[f64]], outputs: list[i32]):
+    Width: Const[i32] = 500 # x-axis limits [0, 499]
+    Height: Const[i32] = 500 # y-axis limits [0, 499]
+    Screen: i32[Height, Width] = empty((Height, Width), dtype=int32)
+    Clear(Height, Width, Screen)
+
+    x1: f64 = 2.0
+    y1: f64 = compute_decision_boundary(p, x1)
+    x2: f64 = -2.0
+    y2: f64 = compute_decision_boundary(p, x2)
+
+    # center the graph using the following offset
+    scale_offset: f64 = Width / 4
+    shift_offset: f64 = Width / 2
+    x1 *= scale_offset
+    y1 *= scale_offset
+    x2 *= scale_offset
+    y2 *= scale_offset
+
+    # print (x1, y1, x2, y2)
+    Line(Height, Width, Screen, i32(x1 + shift_offset), i32(y1 + shift_offset), i32(x2 + shift_offset), i32(y2 + shift_offset))
+
+    i: i32
+    point_size: i32 = 5
+    for i in range(len(input_vectors)):
+        input_vectors[i][0] *= scale_offset
+        input_vectors[i][1] *= scale_offset
+        input_vectors[i][0] += shift_offset
+        input_vectors[i][1] += shift_offset
+        if outputs[i] == 1:
+            x: i32 = i32(input_vectors[i][0])
+            y: i32 = i32(input_vectors[i][1])
+            Line(Height, Width, Screen, x - point_size, y, x + point_size, y)
+            Line(Height, Width, Screen, x, y - point_size, x, y + point_size)
+        else:
+            Circle(Height, Width, Screen, i32(input_vectors[i][0]), i32(input_vectors[i][1]), f64(point_size))
+
+    Display(Height, Width, Screen)
 
 def main0():
     p: Perceptron
@@ -17,4 +65,6 @@ def main0():
     assert p.cur_accuracy > 50.0
     assert p.epochs_cnt > 1
 
+    plot_graph(p, input_vectors, outputs)
+
 main0()