mm2gv
Convert mmdasm disassembly to Graphviz dot format
TLDR
Convert a graph from mm to gv format
Convert a graph using stdin and stdout
Display help
SYNOPSIS
mm2gv [options] [infile]
PARAMETERS
-o
Specifies the name of the output DOT file. If not provided, output is written to standard output.
-s
Sets a floating-point scale factor for node separation in the generated graph. A larger scale value tends to spread nodes further apart.
-N
Defines the shape of the nodes representing rows and columns in the graph. Common shapes include box, circle, ellipse, etc. Refer to the dot man page for a full list of available node shapes.
-E
Determines the visual style of the edges connecting nodes. Examples include solid, dotted, dashed, bold. Refer to the dot man page for more details on edge styles.
-V
Prints the version information of the mm2gv command to standard error.
-?
Prints a brief usage message, listing the available options.
DESCRIPTION
mm2gv is a utility from the Graphviz suite designed to visualize sparse matrices. It reads a matrix in the standard Matrix Market format (typically `.mtx` files), which describes the structure of sparse matrices, and converts it into a Graphviz DOT language file. The resulting DOT file represents the matrix's sparsity pattern as a graph: rows and columns are depicted as nodes, and non-zero entries in the matrix are represented as edges connecting these nodes. This conversion allows users to leverage Graphviz layout engines (like dot, neato, etc.) to generate graphical representations (e.g., PNG, SVG) that clearly illustrate the distribution of non-zero elements. It's particularly useful for analyzing the structure of large, sparse matrices common in scientific computing and numerical analysis, providing an intuitive visual insight into their underlying graph structure.
CAVEATS
While mm2gv effectively visualizes sparse matrices, rendering very large matrices (with millions of non-zero entries) can produce extremely dense graphs that are difficult to interpret or even render by Graphviz layout engines due to computational complexity and visual clutter. Users should be mindful of the input matrix size and consider sampling or alternative visualization techniques for extremely large datasets.
INPUT FORMAT: MATRIX MARKET
The Matrix Market format is a simple, human-readable file format for representing sparse matrices. It is widely used in scientific computing and provides a standardized way to exchange matrix data. mm2gv expects the input file to conform to this standard, typically providing the matrix dimensions and a list of non-zero elements with their row, column, and value.
OUTPUT FORMAT: GRAPHVIZ DOT
The Graphviz DOT language is a plain text graph description language. mm2gv translates the sparse matrix structure into a DOT graph, where matrix rows and columns become nodes, and non-zero entries become edges. This DOT file can then be processed by other Graphviz tools (like dot, neato) to generate various graphical outputs such as PNG, SVG, PDF, etc.
SPARSITY PATTERN VISUALIZATION
The primary use of mm2gv is to visualize the sparsity pattern of a matrix. This pattern reveals the distribution of non-zero elements, which can be critical for understanding a matrix's properties, optimizing algorithms, or identifying underlying network structures. By converting this pattern into a visual graph, mm2gv makes complex matrix structures intuitively accessible.
HISTORY
mm2gv is an integral part of the Graphviz (Graph Visualization Software) project, which was originally developed at AT&T Labs Research. Graphviz provides a robust set of tools for graph drawing, and mm2gv was created to extend its capabilities to the domain of scientific computing, specifically for visualizing the inherent graph structures within sparse matrices. Its development underscores the importance of visual analysis in understanding complex data structures prevalent in fields like numerical linear algebra and network science. It has been part of the Graphviz distribution for many years, evolving alongside the core library to maintain compatibility and utility.