Creating a Scientific Calculator in C with Dev-C

Developing a scientific or advanced calculator using C programming language with Dev-C can be both enjoyable and educational. This guide will walk you through the process, starting from scratch to adding more advanced features as you progress. Aim to begin with a text-based calculator, then move towards integrating a graphical user interface (GUI), and finally, include basic graphing capabilities. This project is designed to be manageable in a one or two week timeframe, allowing you to gradually grow the functionality of your calculator.

Step 1: Setting Up Your Environment

To begin, ensure you have Dev-C installed. Dev-C is a free C/C IDE that works on Windows. If you do not have it, you can download it from the official website. Once installed, open the IDE and create a new project. Name it something relevant, such as “advanced_calculator.”

Step 2: Basic Text-Based Calculator

Your first goal is to create a simple calculator that can handle basic arithmetic operations like addition, subtraction, multiplication, and division. This will form the foundation of your more advanced calculator.

#includestdio.h
int main() {
    float num1, num2, result;
    char operation;
    printf(Enter operation: );
    scanf(%c, operation);
    printf(Enter first number: );
    scanf(quot%f, num1);
    printf(Enter second number: );
    scanf(quot%f, num2);
    switch(operation) {
        case ' ':
            result  num1   num2;
            break;
        case '-':
            result  num1 - num2;
            break;
        case '*':
            result  num1 * num2;
            break;
        case '/':
            if (num2 ! 0)
                result  num1 / num2;
            else {
                printf(Error: Division by zero is not allowed.
);
                return 1;
            }
            break;
        default:
            printf(Invalid operation.
);
            return 1;
    }
    printf(Result: %f
, result);
    return 0;
}

This code covers basic arithmetic operations and handles division by zero errors appropriately. You can run this code in Dev-C and test its functionality by entering different operations and numbers.

Step 3: Building a Graphical User Interface (GUI)

Once your text-based calculator is stable, the next step is to integrate a GUI to make the calculator more user-friendly. For this, you can use a library like wxWidgets which is compatible with Dev-C .

First, include the necessary headers and link the needed libraries:

#include wx/wx.h
class MyFrame : public wxFrame {
public:
    MyFrame(const wxString title);
};
MyFrame::MyFrame(const wxString title) : wxFrame(NULL, wxID_ANY, title, wxDefaultPosition, wxSize(300, 200)) {
    wxPanel *panel  new wxPanel(this, wxID_ANY);
    wxStaticText *number1Text  new wxStaticText(panel, wxID_ANY, Enter first number: , wxPoint(20, 20));
    wxStaticText *number2Text  new wxStaticText(panel, wxID_ANY, Enter second number: , wxPoint(20, 60));
    wxStaticText *operationText  new wxStaticText(panel, wxID_ANY, Select operation: , wxPoint(20, 100));
    wxTextCtrl *number1Ctrl  new wxTextCtrl(panel, wxID_ANY, , wxPoint(140, 20), wxDefaultSize, 0);
    wxTextCtrl *number2Ctrl  new wxTextCtrl(panel, wxID_ANY, , wxPoint(140, 60), wxDefaultSize, 0);
    wxChoice *operationCtrl  new wxChoice(panel, wxID_ANY, wxPoint(140, 100), wxDefaultSize, wxArrayString{wxT( ), wxT(-), wxT(*), wxT(/)}, 0);
    wxButton *calculateButton  new wxButton(panel, wxID_ANY, Calculate, wxPoint(150, 140));
    calculateButton-Connect(wxID_ANY, wxEVT_COMMAND_BUTTON_CLICKED, wxCommandEventHandler(MyFrame::OnCalculate), NULL, this);
}
void MyFrame::OnCalculate(wxCommandEvent event) {
    float num1  std::stof(number1Ctrl-GetValue().ToStdString());
    float num2  std::stof(number2Ctrl-GetValue().ToStdString());
    char operation  operationCtrl-GetStringSelection().front();
    float result  0;
    switch (operation) {
        case ' ': result  num1   num2; break;
        case '-': result  num1 - num2; break;
        case '*': result  num1 * num2; break;
        case '/': if (num2 ! 0) result  num1 / num2; else wxLogError(Error: Division by zero is not allowed.); break;
        default: wxLogError(Invalid operation.); break;
    }
    wxMessageDialog dialog(this, Result:    std::to_string(result), Result, wxICON_INFORMATION | wxOK);
    ();
}

This sample code sets up a basic GUI with text fields and a dropdown menu for operations. When the "Calculate" button is clicked, it performs the selected operation and displays the result.

Step 4: Adding Graphing Capabilities

To include graphing capabilities, you might want to use a library that supports fast graphics and plotting, such as COIN-OR. For simplicity, you can start by integrating a basic plotting mechanism using the libraries provided by wxWidgets.

Here is an example of how you could integrate this functionality:

#include wx/renderer.h
void MyFrame::OnCalculation(wxCommandEvent event) {
    float num1  std::stof(number1Ctrl-GetValue().ToStdString());
    float num2  std::stof(number2Ctrl-GetValue().ToStdString());
    char operation  operationCtrl-GetStringSelection().front();
    float result  0;
    switch (operation) {
        case ' ': result  num1   num2; break;
        case '-': result  num1 - num2; break;
        case '*': result  num1 * num2; break;
        case '/': if (num2 ! 0) result  num1 / num2; else wxLogError(Error: Division by zero is not allowed.); break;
        default: wxLogError(Invalid operation.); break;
    }
    wxDC* dc  wxGetApp().GetTopWindow()-GetLogicalDC().CreateCompatibleDC();
    wxBitmap* bitmap  new wxBitmap(400, 200, dc-GetDepth());
    wxImage* image  bitmap-ConvertToImage();
    wxRenderer* renderer  wxRendererManager::Get()-GetRenderer(YOUR_RENDERER);
    renderer-PrepareDC(dc);
    renderer-DrawGraph(dc, image, num1, num2, result);
    dc-DrawBitmap(*bitmap, 0, 0);
    wxMessageDialog dialog(this, Result:    std::to_string(result), Result, wxICON_INFORMATION | wxOK);
    ();
}

Note: The actual graphing functionality will need to be implemented by creating a custom renderer class. This sample code provides a framework for how you might integrate the graph.

Additional Tips and Resources

- Tutorials on C and C TutorialsPoint - Comprehensive guides on C, C and GUI programming Dev-C Forum - A community where you can find help and share your progress

Conclusion

Building a scientific or advanced calculator in C with Dev-C is a rewarding project that can significantly enhance your programming skills. Start with a simple text-based calculator and gradually add features like a GUI and graphing capabilities. By following this structured approach, you can create a powerful tool that meets your needs and can serve as a basis for more advanced projects in the future.