PHP & More

A technical blog about programming in PHP and about technology in general: programming, workarounds and troubleshooting

A 4D graph can be used for plotting a graph of a complex function, with complex numbers as its input and output. A complex number can be represented as a pair of two real numbers: A real part and an imaginary part. A magnitude and an argument. An image has a width and a height, …

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Qt allows you to develop a multi-platform application, that you can develop a GUI application on one platform and deploy to many others (if you avoid system-specific extra modules). Qt contains modules for creating widgets from elementary ones to OpenGL 3D, which I will discuss later. In addition it contains module with other functionalities an …

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Having upgraded my FreeBSD system and VirtualBox, I found that VirtualBox does not work when invoked from the window manager’s menu. So, I tried running it from the command line, and got the following message: /usr/local/lib/virtualbox/VirtualBox.so: Undefined symbol “_ZNK6QColor6darkerEi@Qt_5” I tried to search the web for the cause, and found a link to a compatibility …

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