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programming - Basic questions about running Mathematica



  1. Is there a command window and an editor in Mathematica 8 similar to those in Matlab? In Mathematica GUI mode, all I saw is write code and run it in the same notebook.


  2. In my Ubuntu terminal, I successfully started Mathematica by ./math (which is the only way I know by the way and I would also like to know what options are available when starting up).


    When I simply copy and paste the code from Heike , nothing new appears, and when I copy and paste the code of Daniel, it works. Wonder why?





  3. Is it correct that there are exactly two ways of running Mathematica code: in a notebook, and in a Mathematica session running in my Linux terminal?


    Are the notebook way and the GUI mode the same thing?


    What does "kernel" mean in Mathematica?


    What are some basic concepts and common sense of running Mathematica?





Answer



Heike's code produces a graphics output. So if you run it inside a raw kernel (which is what the math command does on linux), it won't display any graphics. Instead you'll see something like --Graphics-- on your screen. To actually display the output, you'll need to load the JavaGraphics package as < before the plot command (this needs to be done only once per session).


Jens has more on running Mathematica without a front-end. Brett Champion also notes the following:




When using JavaGraphics`, graphics are rendered by a child front end and converted to a bitmap format. So most new features of graphics are supported. The exception is that if there are interactive aspects to the graphic (tooltips, mouse-overs, Dynamics), they will effectively be ignored. Visualization functions sometimes have problems since in order for them to work correctly, they have to handle Show and DisplayFunction just right. If you do run across problems with a visualization function when using JavaGraphics` , please file it as a bug.



As for the rest of the questions, I'll refer you to the official documentation that Sjoerd shared, as there is no need to duplicate information.


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