GPLOT Procedure

Example 5: Connecting Plot Data Points

Features:

PLOT statement options:: HMINOR=; LVREF=; VAXIS=; VMINOR=; VREF=

Other features:

GOPTIONS statement option: BORDER

SYMBOL statement

Sample library member:

GPLDTPT1

In this example, the PLOT statement uses a plot request of the type y-variable*x-variable to plot the variable HIGH against the variable YEAR to show the annual highs of the Dow Jones Industrial Average over several decades.

This example uses a SYMBOL statement to specify a plot symbol and connect data points with a straight line. In addition, the example shows how PLOT statement options can add reference lines and modify the axes (AXIS statements are not used).

Program

goptions reset=all border;

data stocks;
   input year high low @@;

   datalines;
1956  521.05  462.35 1957  520.77  419.79
1958  583.65  436.89 1959  679.36  574.46
1960  685.47  568.05 1961  734.91  610.25
1962  726.01  535.76 1963  767.21  646.79
1964  891.71  768.08 1965  969.26  840.59
1966  995.15  744.32 1967  943.08  786.41
1968  985.21  825.13 1969  968.85  769.93
1970  842.00  631.16 1971  950.82  797.97
1972 1036.27  889.15 1973 1051.70  788.31
1974  891.66  577.60 1975  881.81  632.04
1976 1014.79  858.71 1977  999.75  800.85
1978  907.74  742.12 1979  897.61  796.67
1980 1000.17  759.13 1981 1024.05  824.01
1982 1070.55  776.92 1983 1287.20 1027.04
1984 1286.64 1086.57 1985 1553.10 1184.96
1986 1955.57 1502.29 1987 2722.42 1738.74
1988 2183.50 1879.14 1989 2791.41 2144.64
1990 2999.75 2365.10 1991 3168.83 2470.30
1992 3413.21 3136.58 1993 3794.33 3241.95
1994 3978.36 3593.35 1995 5216.47 3832.08
;

title1 "Dow Jones Yearly Highs";
footnote1 j=l "Source: 1997 World Almanac";

symbol1 interpol=join
        value=dot;

proc gplot data=stocks;
   plot high*year / haxis=1955 to 1995 by 5
                    vaxis=0 to 6000 by 1000
                    hminor=3
                    vminor=1

                    vref=1000 3000 5000
                    lvref=2;
run;
quit;

Program Description

Set the graphics environment.

goptions reset=all border;

Create the data set. STOCKS contains yearly highs and lows for the Dow Jones Industrial Average and the dates of the high and low values each year.

data stocks;
   input year high low @@;

   datalines;
1956  521.05  462.35 1957  520.77  419.79
1958  583.65  436.89 1959  679.36  574.46
1960  685.47  568.05 1961  734.91  610.25
1962  726.01  535.76 1963  767.21  646.79
1964  891.71  768.08 1965  969.26  840.59
1966  995.15  744.32 1967  943.08  786.41
1968  985.21  825.13 1969  968.85  769.93
1970  842.00  631.16 1971  950.82  797.97
1972 1036.27  889.15 1973 1051.70  788.31
1974  891.66  577.60 1975  881.81  632.04
1976 1014.79  858.71 1977  999.75  800.85
1978  907.74  742.12 1979  897.61  796.67
1980 1000.17  759.13 1981 1024.05  824.01
1982 1070.55  776.92 1983 1287.20 1027.04
1984 1286.64 1086.57 1985 1553.10 1184.96
1986 1955.57 1502.29 1987 2722.42 1738.74
1988 2183.50 1879.14 1989 2791.41 2144.64
1990 2999.75 2365.10 1991 3168.83 2470.30
1992 3413.21 3136.58 1993 3794.33 3241.95
1994 3978.36 3593.35 1995 5216.47 3832.08
;

Define title and footnote.

title1 "Dow Jones Yearly Highs";
footnote1 j=l "Source: 1997 World Almanac";

Define symbol characteristics. Specifying INTERPOL=JOIN joins the data points with straight lines and the VALUE= option specifies the type of symbol used.

symbol1 interpol=join
        value=dot;

Generate the plot and modify the axis values. The VAXIS= option sets major tick marks for the vertical axis. The HMINOR= and VMINOR= options specify the number of tick marks between major tick marks.

proc gplot data=stocks;
   plot high*year / haxis=1955 to 1995 by 5
                    vaxis=0 to 6000 by 1000
                    hminor=3
                    vminor=1

Add reference lines. The VREF= option draws reference lines on the vertical axis at three marks. TheLVREF= option specifies the line style (dashed) for the lines.

                    vref=1000 3000 5000
                    lvref=2;
run;
quit;