Update app.py

app.py

@@ -1,99 +1,615 @@
-import gradio as gr
-import os
-import requests
-from huggingface_hub import InferenceClient
-
-# Initialize the Hugging Face Inference client for DeepSeek
-def get_inference_client():
-    api_token = os.environ.get("HUGGINGFACE_TOKEN")
-    if not api_token:
-        return None
-    
-    client = InferenceClient(token=api_token)
-    return client
-
-def generate_math_questions(chapter, num_questions=5, difficulty="medium"):
-    """Generate mathematics questions based on the provided chapter/topic"""
-    client = get_inference_client()
-    
-    if not client:
-        return "Error: Hugging Face token not configured. Please set the HUGGINGFACE_TOKEN in your space settings."
-    
-    prompt = f"""Generate {num_questions} {difficulty}-level mathematics questions about {chapter}.
-    
-    For each question:
-    1. Write a clear, well-defined question
-    2. Provide a step-by-step solution
-    3. Include the final answer
-    
-    Format your response as:
-    
-    ## Question 1
-    [Question text]
-    
-    ### Solution
-    [Step-by-step solution]
-    
-    ### Answer
-    [Final answer]
-    
-    ## Question 2
-    ...and so on
-    """
-    
-    try:
-        response = client.text_generation(
-            prompt=prompt,
-            model="deepseek-ai/deepseek-math-7b-instruct",
-            max_new_tokens=2048,
-            temperature=0.7,
-            top_p=0.95,
-        )
-        return response
-    except Exception as e:
-        return f"Error generating questions: {str(e)}\n\nPlease ensure your Hugging Face token has the necessary permissions."
-
-# Create the Gradio interface
-with gr.Blocks(title="Mathematics Question Generator") as demo:
-    gr.Markdown("# 🧮 Mathematics Question Generator")
-    gr.Markdown("Enter a mathematics chapter or topic to generate practice questions with solutions.")
-    
-    with gr.Row():
-        with gr.Column(scale=3):
-            chapter_input = gr.Textbox(
-                label="Mathematics Topic/Chapter",
-                placeholder="e.g., Calculus: Integration by Parts",
-                info="Be specific for better results"
-            )
-            
-            with gr.Row():
-                num_questions = gr.Slider(
-                    minimum=1, 
-                    maximum=10, 
-                    value=5, 
-                    step=1, 
-                    label="Number of Questions"
-                )
-                
-                difficulty = gr.Dropdown(
-                    choices=["elementary", "easy", "medium", "hard", "advanced"],
-                    value="medium",
-                    label="Difficulty Level"
-                )
-            
-            generate_button = gr.Button("Generate Questions", variant="primary")
-    
-    with gr.Row():
-        output = gr.Markdown(label="Generated Questions")
-    
-    generate_button.click(
-        fn=generate_math_questions,
-        inputs=[chapter_input, num_questions, difficulty],
-        outputs=output
-    )
-    
-    gr.Markdown("---")
-    gr.Markdown("Created by Kamagelo Mosia | Powered by DeepSeek and Hugging Face")
-
-# Launch the app
+import gradio as gr
+import json
+import re
+import random
+import time
+import os
+from transformers import pipeline
+from huggingface_hub import HfApi
+
+# Set constants
+DEFAULT_NUM_QUESTIONS = 3
+DEFAULT_DIFFICULTY = "Medium"
+MODEL_GENERATION = "facebook/opt-1.3b"  # Free model for question generation
+MODEL_VERIFICATION = "gpt2-large"       # Free model for verification
+
+# Initialize models (with low memory footprint)
+try:
+    question_generator = pipeline("text-generation", model=MODEL_GENERATION, max_length=1000)
+    question_verifier = pipeline("text-generation", model=MODEL_VERIFICATION, max_length=300)
+except Exception as e:
+    print(f"Model loading error: {str(e)}. Will attempt to load on first use.")
+    question_generator = None
+    question_verifier = None
+
+# Calculus curriculum from James Stewart's textbooks
+calculus_curriculum = [
+    {
+        "chapter": "1. Functions and Models",
+        "subchapters": [
+            "1.1 Four Ways to Represent a Function",
+            "1.2 Mathematical Models",
+            "1.3 New Functions from Old Functions",
+            "1.4 Exponential Functions",
+            "1.5 Inverse Functions and Logarithms",
+            "1.6 Parametric Curves"
+        ],
+        "key_formulas": [
+            "Domain and Range",
+            "Function composition: $(f \\circ g)(x) = f(g(x))$",
+            "Exponential function: $f(x) = a^x$, where $a > 0$",
+            "Natural exponential function: $f(x) = e^x$",
+            "Logarithmic function: $f(x) = \\log_a(x)$, where $a > 0, a \\neq 1$",
+            "Natural logarithm: $f(x) = \\ln(x)$"
+        ]
+    },
+    {
+        "chapter": "2. Limits and Derivatives",
+        "subchapters": [
+            "2.1 The Tangent and Velocity Problems",
+            "2.2 The Limit of a Function",
+            "2.3 Calculating Limits",
+            "2.4 Continuity",
+            "2.5 The Derivative",
+            "2.6 The Derivative as a Function",
+            "2.7 Derivatives of Trigonometric Functions",
+            "2.8 The Chain Rule",
+            "2.9 Implicit Differentiation",
+            "2.10 Related Rates",
+            "2.11 Linear Approximations and Differentials"
+        ],
+        "key_formulas": [
+            "Limit Definition: $\\lim_{x \\to a} f(x) = L$",
+            "Derivative Definition: $f'(x) = \\lim_{h \\to 0} \\frac{f(x+h) - f(x)}{h}$",
+            "Power Rule: $\\frac{d}{dx}(x^n) = nx^{n-1}$",
+            "Product Rule: $\\frac{d}{dx}[f(x)g(x)] = f'(x)g(x) + f(x)g'(x)$",
+            "Quotient Rule: $\\frac{d}{dx}\\left[\\frac{f(x)}{g(x)}\\right] = \\frac{f'(x)g(x) - f(x)g'(x)}{[g(x)]^2}$",
+            "Chain Rule: $\\frac{d}{dx}[f(g(x))] = f'(g(x)) \\cdot g'(x)$"
+        ]
+    },
+    {
+        "chapter": "3. Applications of Differentiation",
+        "subchapters": [
+            "3.1 Maximum and Minimum Values",
+            "3.2 The Mean Value Theorem",
+            "3.3 How Derivatives Affect the Shape of a Graph",
+            "3.4 Indeterminate Forms and L'Hospital's Rule",
+            "3.5 Summary of Curve Sketching",
+            "3.6 Optimization Problems",
+            "3.7 Newton's Method",
+            "3.8 Antiderivatives"
+        ],
+        "key_formulas": [
+            "Critical Points: $f'(x) = 0$ or $f'(x)$ is undefined",
+            "Mean Value Theorem: If $f$ is continuous on $[a, b]$ and differentiable on $(a, b)$, then there exists a $c$ in $(a, b)$ such that $f'(c) = \\frac{f(b) - f(a)}{b - a}$",
+            "Second Derivative Test: If $f'(c) = 0$ and $f''(c) > 0$, then $f$ has a local minimum at $c$",
+            "L'Hospital's Rule: $\\lim_{x \\to a}\\frac{f(x)}{g(x)} = \\lim_{x \\to a}\\frac{f'(x)}{g'(x)}$",
+            "Newton's Method: $x_{n+1} = x_n - \\frac{f(x_n)}{f'(x_n)}$"
+        ]
+    },
+    {
+        "chapter": "4. Integrals",
+        "subchapters": [
+            "4.1 Areas and Distances",
+            "4.2 The Definite Integral",
+            "4.3 The Fundamental Theorem of Calculus",
+            "4.4 Indefinite Integrals and the Net Change Theorem",
+            "4.5 The Substitution Rule"
+        ],
+        "key_formulas": [
+            "Definite Integral: $\\int_a^b f(x)\\,dx = \\lim_{n \\to \\infty} \\sum_{i=1}^{n} f(x_i^*)\\Delta x$",
+            "Fundamental Theorem of Calculus: $\\int_a^b f(x)\\,dx = F(b) - F(a)$ where $F'(x) = f(x)$",
+            "Indefinite Integral: $\\int f(x)\\,dx = F(x) + C$ where $F'(x) = f(x)$",
+            "Power Rule for Integration: $\\int x^n\\,dx = \\frac{x^{n+1}}{n+1} + C$ for $n \\neq -1$",
+            "Substitution Rule: $\\int f(g(x))g'(x)\\,dx = \\int f(u)\\,du$ where $u = g(x)$"
+        ]
+    },
+    {
+        "chapter": "5. Applications of Integration",
+        "subchapters": [
+            "5.1 Areas Between Curves",
+            "5.2 Volumes",
+            "5.3 Volumes by Cylindrical Shells",
+            "5.4 Work",
+            "5.5 Average Value of a Function"
+        ],
+        "key_formulas": [
+            "Area Between Curves: $\\int_a^b [f(x) - g(x)]\\,dx$ where $f(x) \\geq g(x)$",
+            "Volume by Disk Method: $V = \\pi\\int_a^b [R(x)]^2\\,dx$",
+            "Volume by Washer Method: $V = \\pi\\int_a^b [(R(x))^2 - (r(x))^2]\\,dx$",
+            "Volume by Cylindrical Shells: $V = 2\\pi\\int_a^b xf(x)\\,dx$ for rotation about y-axis",
+            "Average Value of $f$ on $[a,b]$: $f_{avg} = \\frac{1}{b-a}\\int_a^b f(x)\\,dx$",
+            "Work: $W = \\int_a^b F(x)\\,dx$"
+        ]
+    },
+    {
+        "chapter": "6. Techniques of Integration",
+        "subchapters": [
+            "6.1 Integration by Parts",
+            "6.2 Trigonometric Integrals",
+            "6.3 Trigonometric Substitution",
+            "6.4 Integration of Rational Functions by Partial Fractions",
+            "6.5 Strategy for Integration",
+            "6.6 Approximate Integration",
+            "6.7 Improper Integrals"
+        ],
+        "key_formulas": [
+            "Integration by Parts: $\\int u\\,dv = uv - \\int v\\,du$",
+            "Trigonometric Integrals: $\\int \\sin^n x \\cos^m x\\,dx$ (various formulas)",
+            "Trig Substitution: $x = a\\sin\\theta$ for $\\sqrt{a^2-x^2}$, $x = a\\tan\\theta$ for $\\sqrt{a^2+x^2}$",
+            "Partial Fractions: $\\frac{P(x)}{Q(x)} = \\frac{A}{(x-a)} + \\frac{B}{(x-a)^2} + \\frac{Cx+D}{x^2+bx+c} + ...$",
+            "Improper Integrals: $\\int_a^{\\infty} f(x)\\,dx = \\lim_{t \\to \\infty} \\int_a^t f(x)\\,dx$"
+        ]
+    },
+    {
+        "chapter": "7. Differential Equations",
+        "subchapters": [
+            "7.1 Modeling with Differential Equations",
+            "7.2 Direction Fields and Euler's Method",
+            "7.3 Separable Equations",
+            "7.4 Models for Population Growth",
+            "7.5 Linear Equations",
+            "7.6 Predator-Prey Systems"
+        ],
+        "key_formulas": [
+            "General form of a first-order differential equation: $\\frac{dy}{dx} = f(x, y)$",
+            "Separable equation: $\\frac{dy}{dx} = g(x)h(y)$ → $\\int \\frac{1}{h(y)}dy = \\int g(x)dx + C$",
+            "First-order linear differential equation: $\\frac{dy}{dx} + P(x)y = Q(x)$",
+            "Integrating factor method: Multiply by $e^{\\int P(x)dx}$",
+            "Euler's Method: $y_{n+1} = y_n + hf(x_n, y_n)$"
+        ]
+    },
+    {
+        "chapter": "8. Infinite Sequences and Series",
+        "subchapters": [
+            "8.1 Sequences",
+            "8.2 Series",
+            "8.3 The Integral Test and Estimates of Sums",
+            "8.4 The Comparison Tests",
+            "8.5 Alternating Series",
+            "8.6 Absolute Convergence and the Ratio and Root Tests",
+            "8.7 Strategy for Testing Series",
+            "8.8 Power Series",
+            "8.9 Representations of Functions as Power Series",
+            "8.10 Taylor and Maclaurin Series"
+        ],
+        "key_formulas": [
+            "Geometric Series: $\\sum_{n=0}^{\\infty} ar^n = \\frac{a}{1-r}$ if $|r| < 1$",
+            "Taylor Series: $f(x) = \\sum_{n=0}^{\\infty} \\frac{f^{(n)}(a)}{n!}(x-a)^n$",
+            "Maclaurin Series: $f(x) = \\sum_{n=0}^{\\infty} \\frac{f^{(n)}(0)}{n!}x^n$",
+            "Common Maclaurin Series: $e^x = \\sum_{n=0}^{\\infty} \\frac{x^n}{n!}$, $\\sin(x) = \\sum_{n=0}^{\\infty} \\frac{(-1)^n}{(2n+1)!}x^{2n+1}$",
+            "Ratio Test: $\\lim_{n \\to \\infty} |\\frac{a_{n+1}}{a_n}| < 1$ implies convergence"
+        ]
+    },
+    {
+        "chapter": "9. Parametric Equations and Polar Coordinates",
+        "subchapters": [
+            "9.1 Parametric Curves",
+            "9.2 Calculus with Parametric Curves",
+            "9.3 Polar Coordinates",
+            "9.4 Areas and Lengths in Polar Coordinates",
+            "9.5 Conic Sections"
+        ],
+        "key_formulas": [
+            "Parametric curve: $x = f(t)$, $y = g(t)$",
+            "Arc length of parametric curve: $L = \\int_a^b \\sqrt{[f'(t)]^2 + [g'(t)]^2}\\,dt$",
+            "Polar to rectangular coordinates: $x = r\\cos\\theta$, $y = r\\sin\\theta$",
+            "Rectangular to polar coordinates: $r = \\sqrt{x^2 + y^2}$, $\\theta = \\arctan(\\frac{y}{x})$",
+            "Area in polar coordinates: $A = \\frac{1}{2}\\int_{\\alpha}^{\\beta} [r(\\theta)]^2\\,d\\theta$"
+        ]
+    },
+    {
+        "chapter": "10. Vectors and the Geometry of Space",
+        "subchapters": [
+            "10.1 Three-Dimensional Coordinate Systems",
+            "10.2 Vectors",
+            "10.3 The Dot Product",
+            "10.4 The Cross Product",
+            "10.5 Equations of Lines and Planes",
+            "10.6 Cylinders and Quadric Surfaces"
+        ],
+        "key_formulas": [
+            "Dot Product: $\\vec{a} \\cdot \\vec{b} = |\\vec{a}||\\vec{b}|\\cos\\theta$",
+            "Cross Product: $\\vec{a} \\times \\vec{b} = |\\vec{a}||\\vec{b}|\\sin\\theta\\,\\vec{n}$",
+            "Equation of a line: $\\vec{r} = \\vec{r_0} + t\\vec{v}$",
+            "Equation of a plane: $\\vec{n} \\cdot (\\vec{r} - \\vec{r_0}) = 0$ or $ax + by + cz + d = 0$",
+            "Distance from point to plane: $d = \\frac{|ax_0 + by_0 + cz_0 + d|}{\\sqrt{a^2 + b^2 + c^2}}$"
+        ]
+    },
+    {
+        "chapter": "11. Vector Functions",
+        "subchapters": [
+            "11.1 Vector Functions and Space Curves",
+            "11.2 Derivatives and Integrals of Vector Functions",
+            "11.3 Arc Length and Curvature",
+            "11.4 Motion in Space: Velocity and Acceleration"
+        ],
+        "key_formulas": [
+            "Vector function: $\\vec{r}(t) = x(t)\\vec{i} + y(t)\\vec{j} + z(t)\\vec{k}$",
+            "Derivative of vector function: $\\vec{r}'(t) = x'(t)\\vec{i} + y'(t)\\vec{j} + z'(t)\\vec{k}$",
+            "Arc length: $L = \\int_a^b |\\vec{r}'(t)|\\,dt$",
+            "Unit tangent vector: $\\vec{T}(t) = \\frac{\\vec{r}'(t)}{|\\vec{r}'(t)|}$",
+            "Curvature: $\\kappa = \\frac{|\\vec{T}'(t)|}{|\\vec{r}'(t)|}$",
+            "Acceleration: $\\vec{a}(t) = \\vec{r}''(t)$"
+        ]
+    },
+    {
+        "chapter": "12. Partial Derivatives",
+        "subchapters": [
+            "12.1 Functions of Several Variables",
+            "12.2 Limits and Continuity",
+            "12.3 Partial Derivatives",
+            "12.4 Tangent Planes and Linear Approximations",
+            "12.5 The Chain Rule",
+            "12.6 Directional Derivatives and the Gradient Vector",
+            "12.7 Maximum and Minimum Values",
+            "12.8 Lagrange Multipliers"
+        ],
+        "key_formulas": [
+            "Partial derivative: $\\frac{\\partial f}{\\partial x}(x_0, y_0)$",
+            "Gradient: $\\nabla f = \\frac{\\partial f}{\\partial x}\\vec{i} + \\frac{\\partial f}{\\partial y}\\vec{j} + \\frac{\\partial f}{\\partial z}\\vec{k}$",
+            "Directional derivative: $D_\\vec{u}f = \\nabla f \\cdot \\vec{u}$",
+            "Tangent plane: $z - z_0 = f_x(x_0, y_0)(x - x_0) + f_y(x_0, y_0)(y - y_0)$",
+            "Chain Rule: $\\frac{dz}{dt} = \\frac{\\partial z}{\\partial x}\\frac{dx}{dt} + \\frac{\\partial z}{\\partial y}\\frac{dy}{dt}$"
+        ]
+    },
+    {
+        "chapter": "13. Multiple Integrals",
+        "subchapters": [
+            "13.1 Double Integrals over Rectangles",
+            "13.2 Iterated Integrals",
+            "13.3 Double Integrals over General Regions",
+            "13.4 Double Integrals in Polar Coordinates",
+            "13.5 Applications of Double Integrals",
+            "13.6 Triple Integrals",
+            "13.7 Triple Integrals in Cylindrical Coordinates",
+            "13.8 Triple Integrals in Spherical Coordinates",
+            "13.9 Change of Variables in Multiple Integrals"
+        ],
+        "key_formulas": [
+            "Double integral: $\\iint_R f(x,y)\\,dA = \\int_a^b \\int_c^d f(x,y)\\,dy\\,dx$",
+            "Area in polar coordinates: $\\iint_R f(r,\\theta)\\,dA = \\int_{\\alpha}^{\\beta} \\int_{h_1(\\theta)}^{h_2(\\theta)} f(r,\\theta)\\,r\\,dr\\,d\\theta$",
+            "Triple integral: $\\iiint_E f(x,y,z)\\,dV$",
+            "Cylindrical coordinates: $\\iiint_E f(x,y,z)\\,dV = \\iiint_E f(r\\cos\\theta, r\\sin\\theta, z)\\,r\\,dr\\,d\\theta\\,dz$",
+            "Spherical coordinates: $\\iiint_E f(x,y,z)\\,dV = \\iiint_E f(\\rho\\sin\\phi\\cos\\theta, \\rho\\sin\\phi\\sin\\theta, \\rho\\cos\\phi)\\,\\rho^2\\sin\\phi\\,d\\rho\\,d\\phi\\,d\\theta$"
+        ]
+    },
+    {
+        "chapter": "14. Vector Calculus",
+        "subchapters": [
+            "14.1 Vector Fields",
+            "14.2 Line Integrals",
+            "14.3 The Fundamental Theorem for Line Integrals",
+            "14.4 Green's Theorem",
+            "14.5 Curl and Divergence",
+            "14.6 Surface Integrals",
+            "14.7 Stokes' Theorem",
+            "14.8 The Divergence Theorem"
+        ],
+        "key_formulas": [
+            "Line integral of scalar function: $\\int_C f(x,y,z)\\,ds = \\int_a^b f(\\vec{r}(t))|\\vec{r}'(t)|\\,dt$",
+            "Line integral of vector field: $\\int_C \\vec{F} \\cdot d\\vec{r} = \\int_a^b \\vec{F}(\\vec{r}(t)) \\cdot \\vec{r}'(t)\\,dt$",
+            "Green's Theorem: $\\oint_C (P\\,dx + Q\\,dy) = \\iint_D (\\frac{\\partial Q}{\\partial x} - \\frac{\\partial P}{\\partial y})\\,dA$",
+            "Divergence: $\\text{div}\\,\\vec{F} = \\nabla \\cdot \\vec{F} = \\frac{\\partial P}{\\partial x} + \\frac{\\partial Q}{\\partial y} + \\frac{\\partial R}{\\partial z}$",
+            "Curl: $\\text{curl}\\,\\vec{F} = \\nabla \\times \\vec{F}$",
+            "Stokes' Theorem: $\\int_S (\\nabla \\times \\vec{F}) \\cdot d\\vec{S} = \\oint_C \\vec{F} \\cdot d\\vec{r}$",
+            "Divergence Theorem: $\\iiint_E (\\nabla \\cdot \\vec{F})\\,dV = \\iint_{\\partial E} \\vec{F} \\cdot d\\vec{S}$"
+        ]
+    }
+]
+
+def load_models_if_needed():
+    """Ensures models are loaded when needed"""
+    global question_generator, question_verifier
+    
+    if question_generator is None:
+        try:
+            question_generator = pipeline("text-generation", model=MODEL_GENERATION, max_length=1000)
+        except Exception as e:
+            return f"Error loading question generator: {str(e)}"
+    
+    if question_verifier is None:
+        try:
+            question_verifier = pipeline("text-generation", model=MODEL_VERIFICATION, max_length=300)
+        except Exception as e:
+            return f"Error loading question verifier: {str(e)}"
+    
+    return None
+
+def get_chapter_summary(chapter_idx, subchapter_idx=None):
+    """Get summary of selected chapter and subchapter"""
+    if chapter_idx < 0 or chapter_idx >= len(calculus_curriculum):
+        return "Invalid chapter selection."
+    
+    chapter = calculus_curriculum[chapter_idx]
+    
+    if subchapter_idx is None or subchapter_idx < 0 or subchapter_idx >= len(chapter["subchapters"]):
+        # Return chapter summary only
+        summary = f"# {chapter['chapter']}\n\n"
+        summary += "## Key Formulas\n"
+        for formula in chapter.get("key_formulas", []):
+            summary += f"- {formula}\n"
+        return summary
+    
+    # Return specific subchapter
+    subchapter = chapter["subchapters"][subchapter_idx]
+    summary = f"# {chapter['chapter']}\n## {subchapter}\n\n"
+    summary += "### Key Formulas\n"
+    for formula in chapter.get("key_formulas", []):
+        summary += f"- {formula}\n"
+    
+    return summary
+
+def generate_question_prompt(chapter, subchapter, difficulty, num_questions=3):
+    """Generate a prompt for the model to create questions"""
+    prompt = f"""Create {num_questions} university-level mathematics questions about {subchapter} from {chapter} at {difficulty} difficulty.
+
+For each question:
+1. Write a clear, university-level calculus problem that requires understanding of the concepts and techniques.
+2. Include a step-by-step solution showing all work and mathematical reasoning.
+3. Provide the final answer.
+
+Format your response exactly as follows:
+
+## Question 1
+[Question text]
+
+### Solution
+Step 1: [First step of solution]
+Step 2: [Second step]
+...
+
+### Answer
+[Final answer]
+
+## Question 2
+...
+
+Make sure all mathematics is correct and your solution steps are clear and logical.
+"""
+    return prompt
+
+def verify_question(question_text, solution_text):
+    """Verify if the question and solution are mathematically sound"""
+    error_msg = load_models_if_needed()
+    if error_msg:
+        return False, error_msg
+    
+    verification_prompt = f"""Verify if this calculus question and solution are mathematically correct:
+    
+Question: {question_text}
+
+Solution: {solution_text}
+
+Is the solution mathematically correct? Answer Yes or No and briefly explain why."""
+
+    try:
+        # Get verification response
+        verification = question_verifier(verification_prompt, max_length=300)[0]['generated_text']
+        
+        # Check response for indication that the solution is correct
+        if "yes" in verification.lower() and "incorrect" not in verification.lower() and "error" not in verification.lower():
+            return True, "Verification passed"
+        else:
+            # Extract the explanation for why it's incorrect
+            explanation = verification.split("No")[1] if "No" in verification else "Unable to determine specific issue"
+            return False, f"Verification failed: {explanation}"
+    except Exception as e:
+        return False, f"Error during verification: {str(e)}"
+
+def generate_questions(chapter_index, subchapter_index, difficulty, num_questions):
+    """Generate mathematics questions based on chapter/subchapter"""
+    error_msg = load_models_if_needed()
+    if error_msg:
+        return f"## Error Loading Models\n\n{error_msg}\n\nPlease try again later or contact the administrator."
+
+    # Get chapter and subchapter information
+    if chapter_index < 0 or chapter_index >= len(calculus_curriculum):
+        return "Please select a valid chapter."
+        
+    chapter = calculus_curriculum[chapter_index]
+    
+    if subchapter_index < 0 or subchapter_index >= len(chapter["subchapters"]):
+        return "Please select a valid subchapter."
+    
+    subchapter = chapter["subchapters"][subchapter_index]
+    
+    # Generate prompt for the model
+    prompt = generate_question_prompt(chapter["chapter"], subchapter, difficulty, num_questions)
+    
+    try:
+        # Generate questions
+        result = question_generator(prompt, max_length=1500, do_sample=True, 
+                                   temperature=0.7, top_p=0.85, num_return_sequences=1)[0]['generated_text']
+        
+        # Extract generated questions and solutions
+        result = result.replace(prompt, "")
+        
+        # Basic formatting fixes
+        result = re.sub(r'#+\s*Question', '## Question', result)
+        result = re.sub(r'#+\s*Solution', '### Solution', result)
+        result = re.sub(r'#+\s*Answer', '### Answer', result)
+        
+        # Check if we got properly formatted output
+        if "## Question" not in result:
+            # Fallback to template questions for the topic
+            result = generate_fallback_questions(chapter["chapter"], subchapter, num_questions)
+        
+        # Add chapter summary at the top
+        summary = get_chapter_summary(chapter_index, subchapter_index)
+        result = f"{summary}\n\n# Generated Questions\n\n{result}"
+        
+        return result
+        
+    except Exception as e:
+        return f"Error generating questions: {str(e)}\n\nPlease try again or select a different topic."
+
+def generate_fallback_questions(chapter, subchapter, num_questions):
+    """Generate fallback questions when model generation fails"""
+    # Basic templates for different calculus topics
+    if "Limits" in chapter or "Limits" in subchapter:
+        questions = [
+            {
+                "question": "Evaluate the limit: $\\lim_{x \\to 2} \\frac{x^3 - 8}{x - 2}$",
+                "solution": "Step 1: Note that this is an indeterminate form (0/0) when x = 2.\n" +
+                           "Step 2: Factor the numerator: $x^3 - 8 = (x - 2)(x^2 + 2x + 4)$\n" +
+                           "Step 3: Simplify: $\\lim_{x \\to 2} \\frac{(x - 2)(x^2 + 2x + 4)}{x - 2} = \\lim_{x \\to 2} (x^2 + 2x + 4)$\n" +
+                           "Step 4: Evaluate by direct substitution: $2^2 + 2(2) + 4 = 4 + 4 + 4 = 12$",
+                "answer": "12"
+            },
+            {
+                "question": "Find the limit: $\\lim_{x \\to 0} \\frac{\\sin(3x)}{x}$",
+                "solution": "Step 1: Rewrite using the limit property $\\lim_{x \\to 0} \\frac{\\sin x}{x} = 1$\n" +
+                           "Step 2: $\\lim_{x \\to 0} \\frac{\\sin(3x)}{x} = \\lim_{x \\to 0} 3 \\cdot \\frac{\\sin(3x)}{3x}$\n" +
+                           "Step 3: Apply the limit property: $3 \\cdot \\lim_{x \\to 0} \\frac{\\sin(3x)}{3x} = 3 \\cdot 1 = 3$",
+                "answer": "3"
+            }
+        ]
+    elif "Derivative" in chapter or "Derivative" in subchapter:
+        questions = [
+            {
+                "question": "Find the derivative of $f(x) = x^3\\ln(x) - \\frac{x^3}{3}$",
+                "solution": "Step 1: Use the product rule on $x^3\\ln(x)$\n" +
+                           "$\\frac{d}{dx}[x^3\\ln(x)] = x^3 \\cdot \\frac{1}{x} + \\ln(x) \\cdot 3x^2$\n" +
+                           "$= x^2 + 3x^2\\ln(x)$\n" +
+                           "Step 2: Find the derivative of $\\frac{x^3}{3}$\n" +
+                           "$\\frac{d}{dx}[\\frac{x^3}{3}] = \\frac{3x^2}{3} = x^2$\n" +
+                           "Step 3: Combine the results\n" +
+                           "$f'(x) = x^2 + 3x^2\\ln(x) - x^2 = 3x^2\\ln(x)$",
+                "answer": "$f'(x) = 3x^2\\ln(x)$"
+            }
+        ]
+    elif "Integration" in chapter or "Integral" in chapter or "Integration" in subchapter or "Integral" in subchapter:
+        questions = [
+            {
+                "question": "Evaluate the integral: $\\int x^2\\ln(x) dx$",
+                "solution": "Step 1: Use integration by parts with $u = \\ln(x)$ and $dv = x^2 dx$\n" +
+                           "Then $du = \\frac{1}{x}dx$ and $v = \\frac{x^3}{3}$\n" +
+                           "Step 2: Apply the formula $\\int u dv = uv - \\int v du$\n" +
+                           "$\\int x^2\\ln(x) dx = \\ln(x) \\cdot \\frac{x^3}{3} - \\int \\frac{x^3}{3} \\cdot \\frac{1}{x} dx$\n" +
+                           "$= \\frac{x^3\\ln(x)}{3} - \\frac{1}{3}\\int x^2 dx$\n" +
+                           "$= \\frac{x^3\\ln(x)}{3} - \\frac{1}{3} \\cdot \\frac{x^3}{3} + C$\n" +
+                           "$= \\frac{x^3\\ln(x)}{3} - \\frac{x^3}{9} + C$",
+                "answer": "$\\frac{x^3\\ln(x)}{3} - \\frac{x^3}{9} + C$"
+            }
+        ]
+    else:
+        # Generic calculus questions
+        questions = [
+            {
+                "question": "Find the critical points of $f(x) = x^3 - 6x^2 + 12x + 5$ and determine their nature.",
+                "solution": "Step 1: Find the derivative: $f'(x) = 3x^2 - 12x + 12$\n" +
+                           "Step 2: Set $f'(x) = 0$ and solve: $3x^2 - 12x + 12 = 0$\n" +
+                           "Step 3: Simplify: $x^2 - 4x + 4 = 0$\n" +
+                           "Step 4: Factor: $(x - 2)^2 = 0$\n" +
+                           "Step 5: Therefore $x = 2$ is a critical point (with multiplicity 2)\n" +
+                           "Step 6: Find the second derivative: $f''(x) = 6x - 12$\n" +
+                           "Step 7: Evaluate at $x = 2$: $f''(2) = 6(2) - 12 = 0$\n" +
+                           "Step 8: Since $f''(2) = 0$, the second derivative test is inconclusive\n" +
+                           "Step 9: Checking $f'(x)$ around $x = 2$:\n" +
+                           "For $x < 2$, $f'(x) < 0$ and for $x > 2$, $f'(x) > 0$\n" +
+                           "Step 10: Therefore, $x = 2$ is a point of inflection",
+                "answer": "$x = 2$ is a critical point and an inflection point"
+            }
+        ]
+    
+    # Get a random subset of questions or duplicate if we need more
+    result_questions = []
+    for i in range(num_questions):
+        idx = i % len(questions)
+        q = questions[idx]
+        result_questions.append({
+            "id": i+1,
+            "question": q["question"],
+            "solution": q["solution"],
+            "answer": q["answer"]
+        })
+    
+    # Format the output
+    result = ""
+    for q in result_questions:
+        result += f"## Question {q['id']}\n{q['question']}\n\n"
+        result += f"### Solution\n{q['solution']}\n\n"
+        result += f"### Answer\n{q['answer']}\n\n"
+    
+    return result
+
+def on_chapter_change(chapter_index):
+    """Update subchapter dropdown based on selected chapter"""
+    if chapter_index < 0 or chapter_index >= len(calculus_curriculum):
+        return gr.Dropdown(choices=[], value=None)
+    
+    subchapters = calculus_curriculum[chapter_index]["subchapters"]
+    return gr.Dropdown(choices=subchapters, value=subchapters[0] if subchapters else None)
+
+def create_interface():
+    """Create the Gradio interface"""
+    # Extract chapter titles for dropdown
+    chapters = [chapter["chapter"] for chapter in calculus_curriculum]
+    
+    with gr.Blocks(title="Calculus Question Generator", theme=gr.themes.Soft()) as demo:
+        gr.Markdown("# 🧮 Calculus Question Generator")
+        gr.Markdown("Generate university-level calculus questions with step-by-step solutions.")
+        
+        with gr.Row():
+            with gr.Column(scale=2):
+                chapter_dropdown = gr.Dropdown(
+                    choices=chapters,
+                    value=chapters[0] if chapters else None,
+                    label="Chapter",
+                    info="Select a chapter from Stewart's Calculus"
+                )
+                
+                subchapter_dropdown = gr.Dropdown(
+                    choices=calculus_curriculum[0]["subchapters"] if calculus_curriculum else [],
+                    value=calculus_curriculum[0]["subchapters"][0] if calculus_curriculum and calculus_curriculum[0]["subchapters"] else None,
+                    label="Subchapter",
+                    info="Select a specific subchapter"
+                )
+                
+                with gr.Row():
+                    num_questions = gr.Slider(
+                        minimum=1,
+                        maximum=5,
+                        value=DEFAULT_NUM_QUESTIONS,
+                        step=1,
+                        label="Number of Questions"
+                    )
+                    
+                    difficulty = gr.Dropdown(
+                        choices=["Easy", "Medium", "Hard", "Advanced"],
+                        value=DEFAULT_DIFFICULTY,
+                        label="Difficulty Level"
+                    )
+                
+                generate_button = gr.Button("Generate Questions", variant="primary")
+                
+        output = gr.Markdown(label="Generated Questions & Solutions")
+        
+        # Handle chapter selection change
+        chapter_dropdown.change(
+            fn=on_chapter_change,
+            inputs=[chapter_dropdown],
+            outputs=[subchapter_dropdown]
+        )
+        
+        # Handle generate button click
+        generate_button.click(
+            fn=generate_questions,
+            inputs=[
+                gr.State(lambda: chapters.index(chapter_dropdown.value) if chapter_dropdown.value in chapters else 0),
+                gr.State(lambda: calculus_curriculum[chapters.index(chapter_dropdown.value) if chapter_dropdown.value in chapters else 0]["subchapters"].index(subchapter_dropdown.value) if subchapter_dropdown.value in calculus_curriculum[chapters.index(chapter_dropdown.value) if chapter_dropdown.value in chapters else 0]["subchapters"] else 0),
+                difficulty,
+                num_questions
+            ],
+            outputs=[output]
+        )
+        
+        gr.Markdown("---")
+        gr.Markdown("Created by Kamagelo Mosia | Based on James Stewart's Calculus curriculum")
+    
+    return demo
+
+# Create and launch the interface
+demo = create_interface()
 demo.launch()