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1.2       bowersj2    1: \label{Calling_Functions}
1.1       bowersj2    2: 
                      3: With variables, you can store strings or numbers. \textbf{Functions} allow
                      4: you to manipulate these strings or numbers. Functions work like mathematical
                      5: functions: They take some number of arguments in, and return one argument,
                      6: usually a number or a string for our purposes. There are a lot of functions
1.3       www         7: available in LON-CAPA. You can see a complete list at
1.4     ! albertel    8: \ref{all_functions_table}.
1.3       www         9: 
1.1       bowersj2   10: For now, let's just look at some simple examples.
                     11: 
                     12: %
                     13: \begin{figure}
                     14: \begin{lyxcode}
                     15: \$a~=~-3.0;
                     16: 
                     17: \$b~=~\&sin(\$a);
                     18: 
                     19: \$c~=~\&pow(3.0,~\&abs(\$a));
                     20: \end{lyxcode}
                     21: 
                     22: \caption{Some Function Calls\label{Some Function Calls Figure}}
                     23: \end{figure}
                     24: In the \textbf{Script} block, function names start with \textbf{\&}. Some
                     25: example function calls are shown in figure \ref{Some Function Calls Figure}.
                     26: You can see that functions can take either variables, numbers, or the results
                     27: of other function calls as parameters. The \texttt{\&sin} function returns
                     28: the sine of an angle expressed in radians. \texttt{\&pow} raises the first
                     29: parameter to the power of the second parameter. \texttt{\&abs} returns the
                     30: absolute value of the argument.