out = airquality () ¶New York Air Quality Measurements from 1973
Daily air quality measurements in New York, May to September 1973.
OzoneOzone concentration (ppb)
SolarRSolar R (lang)
WindWind (mph)
TempTemperature (degrees F)
MonthMonth (1-12)
DayDay of month (1-31)
New York State Department of Conservation (ozone data) and the National Weather Service (meteorological data).
Chambers, J. M., Cleveland, W. S., Kleiner, B. and Tukey, P. A. (1983). Graphical Methods for Data Analysis. Belmont, CA: Wadsworth.
t = tblish.dataset.airquality
# Plot a scatter-plot plus a fitted line, for each combination of measurements
vars = {"Ozone", "SolarR", "Wind", "Temp" "Month", "Day"};
n_vars = numel (vars);
figure;
for i = 1:n_vars
for j = 1:n_vars
if (i == j)
continue
endif
ix_subplot = (n_vars * (j - 1) + i);
hax = subplot (n_vars, n_vars, ix_subplot);
var_x = vars{i};
var_y = vars{j};
x = t.(var_x);
y = t.(var_y);
scatter (hax, x, y, 10);
# Fit a cubic line to these points
# TODO: Find out exactly what kind of fitted line R's example is using, and
# port that.
hold on
p = polyfit (x, y, 3);
x_hat = unique(x);
p_y = polyval (p, x_hat);
plot (hax, x_hat, p_y, "r");
endfor
endfor