Matvec Users’ Guide

Chapter 5
File Stream Control
Matvec provides a class of input/out stream, which is a substantially limited C++ I/O stream system. A
stream is a logical object associated with a physical device such as disk.
When output is performed, data is not immediately written to the physical device associated with the
stream. Instead, data is stored in an internal buffer until the buffer is full. However, data in the buffer can
be forced out to disk before the buffer is full by using either endl() or flush(). Note that buffering is used to
improve performance. Flushing each line of output using either endl() or flush() decreases efficiency.
5.1 Standard File Streams
There are three standard file streams created automatically each time when Matvec is invoked: cout, cin,
cerr.
5.1.1 cout
not yet available
5.1.2 cin
not yet available
5.1.3 cerr
not yet available
5.2 User Specified File Stream
5.2.1 Creation
f = FileStream("","") creates an object of class FileStream and assign to f. The
"" can be either relative or absolute, and the "" must be one the following or appropriate
combination: out, in, app, noreplace.
5.2.2 Example
> f = FileStream("try.out","out");
> f.out("I am testing MATVEC file stream\n");
> Pi=3.14159;
> f.out("Pi = ", Pi, " 2*Pi = ", 2*Pi,"\n");
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