| Abstract |
This report gives full documentation and serves as a user's manual for INDEX.PLOT, a Fortran computer program designed to calculate the Pollutant Standards Index (PSI). The PSI was proposed in the Federal Register in September 1976 by the Environmental Protection Agency as a nationally uniform air pollution index, and is intended for use by State and local air pollution control agencies under Section 319 of the Clean Air Act. This computer program, which was originally developed to test the structure of PSI, has now been expanded as a general purpose program which can compute daily index values for a month, a season, a year, or longer. The program consists of 563 Fortran statements and contains seven specialized subroutines. By use of the subroutines, the main program: lists the raw data, along with any data set labels; inventories missing values in the data set; plots a time series graph of PSI values on the line printer; calculates statistics for PSI (mean, standard deviation, range, coefficients of skewness and kurtosis); and generates and plots a frequency distribution of PSI values, along with cumulative frequencies, on the line printer. A complete listing of the program is given, along with sample outputs and descriptions of each subroutine. This program can be used for describing air quality trends, comparing data from different monitoring stations, and developing environmental quality profiles. (Color illustrations reproduced in black and white) |
