Tested tool guide
Tested browser tools
Checked August 16, 2026
What Piecewise Function Grapher does, with a checked example
A piecewise function is one formula on part of its domain and a different formula on the rest, and all of its interesting behavior sits at the seams between the parts. This tool takes each branch as a formula plus a domain interval, draws it only over that interval, marks boundary points with filled or hollow circles, and computes the one-sided limits at every breakpoint to report whether the function is continuous there. The point people most often miss: the value at a breakpoint belongs to whichever branch includes it, so a jump, a hole, or an isolated point can all hide at the same x-value.
Worked example
A concrete input and expected output from the current implementation.
Input
f(x) = x^2 for x < 1; 3 - x for x >= 1
->
Expected output
Two branches plotted: the parabola y = x^2 drawn only left of x = 1, ending in a hollow circle at (1, 1); the line y = 3 - x drawn from x = 1 onward, starting with a filled circle at (1, 2). Limits report: left limit 1, right limit 2, value 2, so the limit at x = 1 does not exist and the function is discontinuous there (a jump from height 1 to height 2).
As x approaches 1 from below, x^2 approaches 1, while the branch that owns x = 1 gives 3 - 1 = 2. Because the two sides approach different heights, the graph jumps and continuity fails at x = 1.