MATLAB Programming

4 M-File Programming
City Temp. Heat Index Wind Speed Wind Chill
Boston 43 32 8 37
Chicago 34 27 3 30
Lincoln 25 17 11 16
Denver 15 -5 9 0
Las Vegas 31 22 4 35
San Francisco 52 47 18 42
The information is stored in structure W. The structure has one field for each
column of data:
W = struct('city', {'Bos','Chi','Lin','Dnv','Vgs','SFr'}, ...
'temp', {43, 34, 25, 15, 31, 52}, ...
'heatix', {32, 27, 17, -5, 22, 47}, ...
'wspeed', {8, 3, 11, 9, 4, 18}, ...
'wchill', {37, 30, 16, 0, 35, 42});
To update the data base, you can pass the entire structure, or just one
field with its associated data. In the call shown here, W.wchill is a
comma-separated list:
updateStats(W.wchill);
Passing Arguments in a Cell Array
You can also group arguments into cell arrays. The advantage over structures
is that cell arrays are referenced by index, allowing you to loop through a
cell array and access each argument passed in or out of the function. The
disadvantage is that you don’t have field names to describe each variable.
This example passes several attribute-value arguments to the plot function:
X = -pi:pi/10:pi;
Y = tan(sin(X)) - sin(tan(X));
C{1,1} = 'LineWidth'; C{2,1} = 2;
C{1,2} = 'MarkerEdgeColor'; C{2,2} = 'k';
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