Figure 2
From: Visual data mining based on differential topology: a survey

Singular points of a 2-dimensional scalar field. (a) A peak (index 2). (b) A pass (index 1). (c) A pit (index 0).
From: Visual data mining based on differential topology: a survey
Singular points of a 2-dimensional scalar field. (a) A peak (index 2). (b) A pass (index 1). (c) A pit (index 0).