Scatter Plot of Test Function
The line is a construct. It is not really the function, just a smooth summary of the function. Always keep this in mind.
Recall that we, in fact, generated a sample of points in the input space and corresponding evaluation of those points.
As such, it would be more accurate to create a scatter plot of points; for example:
scatter plot of input vs result for a 1d objective function
from numpy import arange
from matplotlib import pyplot
objective function
def objective(x):
return x**2.0
define range for input
r_min, r_max = -5.0, 5.0
sample input range uniformly at 0.1 increments
inputs = arange(r_min, r_max, 0.1)
compute targets
results = objective(inputs)
create a scatter plot of input vs result
pyplot.scatter(inputs, results)
show the plot
pyplot.show()
Running the example creates a scatter plot of the objective function.
We can see the familiar shape of the function, but we don’t gain anything from plotting the points directly.
The line and the smooth interpolation between the points it provides are more useful as we can draw other points on top of the line, such as the location of the optima or the points sampled by an optimization algorithm.