Weierstrass function
![Plot of Weierstrass function over the interval [−2, 2]. Like fractals, the function exhibits self-similarity: every zoom (red circle) is similar to the global plot.](/Images/godic/202501/30/WeierstrassFunction.svg5203.png")
In mathematics, the Weierstrass function is an example of a pathological real-valued function on the real line. The function has the property of being continuous everywhere but differentiable nowhere. It is named after its discoverer Karl Weierstrass.