MATLAB Programming

Characters and Strings
Formatting Strings
The following MATLAB functions offer the capability to compose a string that
includes ordinary text and data formatted to your specification:
• sprintf — Write formatted data to an output string
• fprintf — Write formatted data to an output file or the command window
• warning — Display formatted data in a warning message
• error — Display formatted data in an error message and abort
• assert —Generateanerrorwhenaconditionisviolated
The syntax of each of these functions includes formatting operators similar
to those used by the printf function in the C programming language. For
example, %s tells MATLAB to interpret an input value as a string, and %d
means to format an integer using decimal notation.
The general formatting syntax for these functions is
functionname(..., format_string, value1, value2, ..., valueN)
where the format_string argument expresses the basic content and
formatting of the final output string, and the value arguments that follow
supply data values to be inserted into the string.
Here is a sample sprintf statement, also showing the resulting output string:
sprintf('The price of %s on %d/%d/%d was $%.2f.', ...
'bread', 7, 1, 2006, 2.49)
ans =
The price of bread on 7/1/2006 was $2.49.
The following sections cover
• “The Format String” on page 2-44
• “Input Value Arguments” on page 2-45
• “The Formatting Operator” on page 2-46
• “Constructing the Formatting Operator” on page 2-47
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