You can construct file names within a loop using the sprintf function (which is usually
more efficient than int2str), and then call the save function without eval. This code
creates 10 files in the current folder:
numFiles = 10;
for n = 1:numFiles
randomData = rand(n);
currentFile = sprintf('myfile%d.mat',n);
save(currentFile,'randomData')
end
For more information, see:
- “Command vs. Function Syntax” on page 1-9
- “Import or Export a Sequence of Files”
Function Names in Variables
A common use of eval is to execute a function when the name of the function is in a
variable character vector. There are two ways to evaluate functions from variables that
are more efficient than using eval:
- Create function handles with the @ symbol or with the str2func function. For
example, run a function from a list stored in a cell array:
examples = {@odedemo,@sunspots,@fitdemo};
n = input('Select an example (1, 2, or 3): ');
examples{n}()- Use the feval function. For example, call a plot function (such as plot, bar, or pie)
with data that you specify at run time:
plotFunction = input('Specify a plotting function: ','s');
data = input('Enter data to plot: ');
feval(plotFunction,data)Field Names in Variables
Access data in a structure with a variable field name by enclosing the expression for the
field in parentheses. For example:
myData.height = [67, 72, 58];
myData.weight = [140, 205, 90];
Alternatives to the eval Function