f(x) =
Presets:
sin(x)+1.5
x^2
exp(-x^2)
abs(x)
1/(1+x^2)
cos(3x)+1.2
a
b
Mode
Riemann
Lebesgue (squares)
Rule
Left
Midpoint
Right
Step / square size (s)
Plot samples
Approx area:
Reference (fine trapezoid):
Lebesgue mode draws
s × s
squares (Δx = Δy = s) stacked under the curve (negative values are clamped to 0 for this visualization).