GNU Info

(gnuplot.info)Expressions

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Enter node , (file) or (file)node

 In general, any mathematical expression accepted by C, FORTRAN, Pascal, or
 BASIC is valid.  The precedence of these operators is determined by the
 specifications of the C programming language.  White space (spaces and tabs)
 is ignored inside expressions.

 Complex constants are expressed as {<real>,<imag>}, where <real> and <imag>
 must be numerical constants.  For example, {3,2} represents 3 + 2i; {0,1}
 represents 'i' itself.  The curly braces are explicitly required here.

 Note that gnuplot uses both "real" and "integer" arithmetic, like FORTRAN and
 C.  Integers are entered as "1", "-10", etc; reals as "1.0", "-10.0", "1e1",
 3.5e-1, etc.  The most important difference between the two forms is in
 division: division of integers truncates: 5/2 = 2; division of reals does
 not: 5.0/2.0 = 2.5.  In mixed expressions, integers are "promoted" to reals
 before evaluation: 5/2e0 = 2.5.  The result of division of a negative integer
 by a positive one may vary among compilers.  Try a test like "print -5/2" to
 determine if your system chooses -2 or -3 as the answer.

 The integer expression "1/0" may be used to generate an "undefined" flag,
 which causes a point to ignored; the `ternary` (Note: Ternary ) operator
 gives an example.

 The real and imaginary parts of complex expressions are always real, whatever
 the form in which they are entered: in {3,2} the "3" and "2" are reals, not
 integers.

Functions

Operators

User-defined