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eval

(/tools/hpmatlab/toolbox/matlab/lang/eval.m)

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EVAL	Execute string containing MATLAB expression.
	EVAL(s), where s is a string, causes MATLAB to execute
	the string as an expression or statement.

	EVAL(s1,s2) provides the ability to catch errors.  It
	executes string s1 and returns if the operation was
	successful. If the operation generates an error,
	string s2 is evaluated before returning. Think of this
	as EVAL('try','catch')
	
	[X,Y,Z,...] = EVAL(s) returns output arguments from the
	expression in string s.

	The input strings to EVAL are often created by 
	concatenating substrings and variables inside square
	brackets. For example:

	Generate a sequence of matrices named M1 through M12:

	    for n = 1:12
	       eval(['M' num2str(n) ' = magic(n)'])
	    end

	Run a selected M-file script.  The strings making up 
	the rows of matrix D must all have the same length.
	
	    D = ['odedemo '
	         'quaddemo'
	         'fitdemo '];
	    n = input('Select a demo number: ');
	    eval(D(n,:))

	Read and process files with names data1.dat, data2.dat, ...

	    k = 0;
	    while 1
	       k = k+1;
	       datak = ['data' int2str(k)];
	       filename = [datak '.dat'];
	       if ~exist(filename), break, end
	       eval(['load ' filename]);
	       X = eval(datak);
	       % Process data in matrix X.
	    end

	See also LASTERR, FEVAL.

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