Update app.py

app.py

@@ -9,38 +9,42 @@ import re
 def preprocess_handwritten_image(pil_img):
     return pil_img.convert('RGB')  # Minimal processing, just convert to RGB
 
-
 # Load Pix2Tex model (once)
 model = LatexOCR()
 
 # Clean LaTeX output
 def clean_latex(latex):
     # Replace \mathcal{X} or \cal X with 'x'
-    latex = re.sub(r'\\(cal|mathcal)\s*X', 'x', latex)
+    latex = re.sub(r'\\(cal|mathcal)\\s*X', 'x', latex)
 
     # Remove curly braces
     latex = latex.replace('{', '').replace('}', '')
     latex = latex.strip().rstrip(',.')
-    
+
     # Replace coefficients like 5\pi with (5*3.1416)
-    latex = re.sub(r'(\d+)\s*\\pi', r'(\1*3.1416)', latex)
+    latex = re.sub(r'(\d+)\\s*\\pi', r'(\1*3.1416)', latex)
     latex = latex.replace(r'\pi', '3.1416')
 
     # Replace coefficients like 5e with (5*2.7183)
-    latex = re.sub(r'(\d+)\s*e', r'(\1*2.7183)', latex)
+    latex = re.sub(r'(\d+)\\s*e', r'(\1*2.7183)', latex)
     latex = re.sub(r'(?<![a-zA-Z0-9])e(?![a-zA-Z0-9])', '2.7183', latex)
 
     # Insert * between number and variable (e.g., 45x → 45*x)
     latex = re.sub(r'(\d)([a-zA-Z])', r'\1*\2', latex)
 
     # Replace number followed by i with number*I
-    latex = re.sub(r'(\d+)\s*i', r'\1*I', latex)
+    latex = re.sub(r'(\d+)\\s*i', r'\1*I', latex)
 
     # Replace standalone i with I
     latex = re.sub(r'(?<![a-zA-Z0-9])i(?![a-zA-Z0-9])', 'I', latex)
 
     # Wrap complex coefficients with variables: (a+bI)x^n → (a+b*I)*x^n
-    latex = re.sub(r'\(([^()]+?)\)\s*([xX](\^\d+)?)', r'(\1)*\2', latex)
+    latex = re.sub(r'\\(([^()]+?)\\)\\s*([xX](\\^\d+)?)', r'(\1)*\2', latex)
+
+    # Fix common OCR mistakes
+    latex = re.sub(r'\bL(\d)', r'1\1', latex)
+    latex = latex.replace('\\pm', '').replace('!', '')
+    latex = re.sub(r'[^\w\s\^\+\-\*/=xX\(\)\.\*]', '', latex)
 
     # Append '=0' if not already present
     if '=' not in latex:
@@ -48,6 +52,17 @@ def clean_latex(latex):
 
     return latex
 
+# Fallback parser if LaTeX parsing fails
+def fallback_parse(cleaned_latex):
+    try:
+        if '=' in cleaned_latex:
+            cleaned_latex = cleaned_latex.split('=')[0]
+        cleaned_latex = cleaned_latex.replace('^', '**')
+        x = sp.symbols('x')
+        expr = eval(cleaned_latex, {"x": x, "I": sp.I, "pi": sp.pi})
+        return sp.Eq(expr, 0)
+    except Exception:
+        return None
 
 # Main function
 def solve_polynomial(image):
@@ -56,10 +71,23 @@ def solve_polynomial(image):
         latex_result = model(img)
         cleaned_latex = clean_latex(latex_result)
 
-        expr = parse_latex(cleaned_latex)
-        output = f"## 📄 Extracted LaTeX\n```\n{latex_result}\n```\n"
+        try:
+            expr = parse_latex(cleaned_latex)
+        except Exception:
+            expr = None
+
+        if not expr:
+            expr = fallback_parse(cleaned_latex)
+
+        if not expr:
+            return f"❌ Could not parse expression from cleaned LaTeX:\n```
+{cleaned_latex}\n```"
+
+        output = f"## 📄 Extracted LaTeX\n```
+{latex_result}\n```\n"
         output += "---\n"
-        output += f"## 🧹 Cleaned LaTeX Used\n```\n{cleaned_latex}\n```\n"
+        output += f"## 🧹 Cleaned LaTeX Used\n```
+{cleaned_latex}\n```\n"
         output += "---\n"
         output += f"## 🧠 Parsed Expression\n\n$$ {sp.latex(expr)} $$\n"
         output += "---\n"
@@ -83,7 +111,7 @@ def solve_polynomial(image):
                 output += "$$\n\\begin{aligned}\n"
                 for i, sol in enumerate(roots, 1):
                     for var, val in sol.items():
-                        output += f"\\text{{Root {i}}}:\\quad {var} &= {sp.latex(val)} \\\\\n"
+                        output += f"\\text{{Root {i}}}:\\quad {var} &= {sp.latex(val)} \\\\n"
                 output += "\\end{aligned}\n$$\n"
 
         else:
@@ -96,7 +124,6 @@ def solve_polynomial(image):
     except Exception as e:
         return f"❌ **Error**: {str(e)}"
 
-
 # Gradio UI
 demo = gr.Interface(
     fn=solve_polynomial,