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The PLplot library has been designed so that it is easy to write programs producing graphical output without having to set up large numbers of parameters. However, more precise control of the results may be necessary, and these are accommodated by providing lower-level routines which change the system defaults. The manual first describes the overall process of producing a graph using the high-level routines (see the Section called Plotting a Simple Graph in Chapter 2). For a discussion of the underlying concepts of the plotting process and an introduction to some of the more complex routines (see Chapter 3). An alphabetical list of the user-accessible PLplot functions with detailed descriptions is given in the reference section of the manual (see Chapter 17).
Because the PLplot kernel is written in C, standard C syntax is used in the description of each PLplot function. The C and Fortran language interfaces are discussed in Appendix \ref{ap:lang}; look there if you have difficulty interpreting the call syntax as described in this manual. The meaning of function (subroutine) arguments is typically the same regardless of whether you are calling from C or Fortran (but there are some exceptions to this). The arguments for each function are usually specified in terms of PLBOOL, PLINT,and PLFLT—these are the internal PLplot representations for logical, integer, and floating point, and are typically a zero (false) or non-zero (true) contained in a long, a long, and a float (or a LOGICAL, INTEGER, and a REAL, for Fortran programmers). See Appendix \ref{ap:lang} for more detail.
Also, you can use PLplot from C++ just as you would from C. No special classes are available at this time, just use it as any other procedural type library. Simply include plplot.h, and invoke as you would from C.
The output devices supported by PLplot are listed in Appendix \ref{ap:dev}, along with description of the device driver--PLplot interface, metafile output, family files, and vt100/tek4010 emulators. In Appendix\ref{ap:sys} the usage and installation for each system supported by PLplot is described (not guaranteed to be entirely up-to-date; check the release notes to be sure).