PRP: a FORTRAN IV interactive plotting program

A computer program, PRP, has been designed to plot any arithmetic combination selected from a set of major and trace element data on a y-x graph. y and x are defined and entered as a program string (y, x) which is interpreted sequentially. Operators ($\text{+, -, 1, /, (}\text{unary}\text{)}$, square root, log₁₀, In_c, antilog₁₀, exponential, integer, absolute value, (,),,) and integer or real numbers may be included. Axis lengths and scales are determined by the user. Five different plotting symbols are available.