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--- matlab_-_introduction [2012/10/06 02:09] – created jochen
+++ matlab_-_introduction [2012/10/08 14:44] – added more info on GUI elements jochen
@@ Line 8: / Line 8: @@
 ===== Language features =====
   * the language is easy to use for prototyping, given its forgiving and user-friendly nature
-    * variables do require a declaration and can be defined and have their datatype and dimension changed at any point within a program
+    * variables don't require a declaration but can be defined and have their datatype and dimension changed at any point within a program
     * numeric variables are, by default, all created with a standard datatype of **''double''**, requiring little (if any) knowledge of numeric datatypes
-    * identifiers can be overloaded (e.g. built-in functions can be replaced by user defined ones)
+    * storage of and access to variable values is organized in workspaces
+    * identifiers can be overloaded (e.g. built-in functions can be replaced by user defined ones), globally or separately in each workspace
   * array indexing is available in multiple ways to simplify element selection (see [[Matlab - datatypes|datatypes and indexing page]])
   * array-based operations are highly optimized for speed and mostly support multiple CPU cores
-  * memory management is built-in (garbage collection on variables no longer in use)
+  * memory management is built-in (workspace-related garbage collection on variables no longer in use)
   * Matlab comes with a vast repository of built-in and built-upon functions for mathematical computations, data in- and output, as well as visualization
   * functions can return more than one output value/variable (without having to resort to compound/struct variables)
@@ Line 20: / Line 21: @@
   * with a built-in interface to compiled code (MEX), Matlab allows to translate computationally intensive operations (recursion, etc.) into compiled code for speedup
   * built-in file format to store the content of variables in a binary format (incl. compression and platform independence)
+==== Built-in functionality ====
+On top of these features, Matlab comes with many, many built-in functions from a variety of fields, among them are
+  * mathematical functions (sum, mean, median, mode, standard deviation/variance, discrete derivatives, convolution, minimum, maximum, etc.)
+  * list and set related functions (sort, unique, intersect, setdiff, union, etc.)
+  * rudimentary statistical functions (histogram, correlation coefficient, detrending, etc.)
+  * matrix operations (inverse, pseudo-inverse, SVD, decomposition, etc.)
+  * graphical output functions (line, polygon, shape, surface, and scatter plot, annotations, etc.)
+  * GUI functions (figures, controls, callback handling, etc.)
+These features make it usually relatively efficient to create code with complex functionality with just a few lines of code.
+==== User-provided toolboxes ====
+Mathworks additionally provides a user-defined toolbox area on their webserver, [[http://www.mathworks.com/matlabcentral/fileexchange/|File Exchange]], where users can upload their functions (or sets of functions, called toolboxes) which often allows users to solve even complex problems with a minimal effort, given that someone has already solved it before.
 ===== GUI elements =====
@@ Line 31: / Line 46: @@
 Additionally, Matlab comes with a built-in Editor, supporting syntax highlighting and augmenting several of the core features of Matlab, as well as a Profiler, a tool to identify bottlenecks in code, i.e. a help to improve the run-time properties (time and memory consumption) of user-written code.
+==== Command line ====
+The command line allows the user to enter commands and inspect returned values (text output intermixed with input). Matlab shows a prompt (**''<nowiki>>></nowiki>''**) during normal operation and an extended prompt for debugging (**''<nowiki>K>></nowiki>''**). The command line offers a few additional functions which are extremely helpful:
+  * pressing the **''cursor-up''** key allows to cycle through previous commands, and if some text is entered before, only entries matching this text are presented
+  * the **''tab''**-key does not produce a tab-character (indentation) but instead Matlab attempts to auto-complete a series of letters to a "known expression" (variable, field, or function name)
+  * when entering expressions with parenthesis (precedence of operations, function arguments, etc.) or brackets/curly braces, Matlab highlights matching pairs to confirm the completeness of the expression
+  * if an expression is incomplete (e.g. a **''for''** loop is constructed, but the final **''end''** keyword is missing), Matlab expects additional input on the next line (after pressing return)
+  * whenever an error is encountered while processing a line of input, Matlab indicates the exact position of the problem with a vertical line below the input (pipe character)
+  * output in the command window supports hyperlinks (in help texts for instance), which gives the user to immediately select a topic of reference for additional information
+  * the **''display''** function (which is automatically called when an expression is not terminated with a semicolon) provides auto-formatting for all built-in datatypes (incl. arrays)
+  * to change the current folder or load a MAT-file, drag-and-drop operations can be performed with either Finder (Mac) or Explorer (Windows), by dragging a folder or MAT-file name into the command prompt window
+==== Command history ====
+The history window is particularly useful when a series of commands is to be converted into an M-file (batch of function file grouping a set of commands/function calls into a new functionality). This can be achieved by selecting several entries (line by line selection) and then using the context menu (right-click or **''CTRL''**-click). To quickly repeat one specific instruction, an entry can also be double-clicked.
+==== Workspace ====
+Equally, the workspace window offers a context menu, which allows to rename variables, delete them from the workspace (same as **''clear VARIABLE''**), save the content of selected variables to disk, or alter their content.
+==== Current folder ====
+The current folder window is a feature-rich file browser, also with additional functionality in the context menu.