使用报告信息对象计算代码行数

打开实时脚本

此示例说明如何使用报告信息对象计算源代码和生成代码中的行数。有关报告信息对象的详细信息，请参阅Access Code Generation Report Information Programmatically。

MATLAB 代码

在此示例中，您将为 MATLAB® 函数 dijkstra 生成代码。此函数使用迪杰斯特拉算法计算从节点到图中每个其他节点的最短路径的长度。

type dijkstra
% DIJKSTRA Find length of shortest path between nodes in a graph
%
% D = dijkstra(A, p) 
% Takes a graph represented by its adjacency matrix 'A' along with a node 
% 'p' as input and returns a vector 'D' containing the length of the 
% shortest path from 'p' to all other nodes in the graph. 

% Copyright 2018 The MathWorks, Inc.
function D = dijkstra(A, p) %#codegen

    narginchk(2,2);
    
    [m, n] = size(A);

    % Assertions to make sure inputs are valid
    assert(m == n, "Input adjacency matrix for graph must be a square matrix");
    assert(rem(p, 1) == 0 && p <= m && p > 0, "Input src must be a node in the graph");
    
    % Initialization
    max = realmax;
    D = repmat(max, 1, m);
    D(p) = 0;
    visited = false(1, m);
    
    for i = 1:m
        % Select next node to visit
        min = max;
        u = -1;
        for v = 1:n
            if ~visited(v) && D(v) <= min
                min = D(v);
                u = v;
            end
        end
        
        % Mark selected node as visited
        visited(u) = true;
        
        %{ 
          Update distances of nodes adjacent to selected node that are yet
          to be visited
        %}
        for v = 1:n
            if(~visited(v) && A(u, v) ~= 0 && D(u) ~= max)
                distVal = D(u) + A(u, v);
                if distVal < D(v)
                    D(v) = distVal;
                end
            end
        end
    end
end

指定一个图的邻接矩阵 A 和遍历该图的开始节点 p。绘制图。调用 dijkstra 以计算从 p 到图中每个节点的最短距离，并显示这些距离。

% Sample adjacency Matrix for graph with 5 nodes
A = [
        0 1 1 0 0; 
        1 0 0 1 1; 
        1 0 0 1 0; 
        0 1 1 0 1; 
        0 1 0 1 0
    ];

% Plot the graph to see how it looks like
G = graph(A, 'omitselfloops');
plot(G, 'EdgeLabel', G.Edges.Weight)

Figure contains an axes object. The axes object contains an object of type graphplot.

% Source node from where graph traversal begins
p = randi(size(A, 1));

% Calculate shortest distance from 'p' to every other node in graph G
D = dijkstra(A, p);

for i=1:numel(D)
    fprintf("Length of shortest path from %d to %d is %d. \n", p, i, D(i));
end
Length of shortest path from 5 to 1 is 2. 
Length of shortest path from 5 to 2 is 1. 
Length of shortest path from 5 to 3 is 2. 
Length of shortest path from 5 to 4 is 1. 
Length of shortest path from 5 to 5 is 0.

导出有关代码生成的信息

报告信息对象提供对代码生成相关信息的编程访问。此对象的属性提供有关代码生成设置、输入文件、生成的文件以及代码生成错误、警告和信息消息的信息。

要将报告信息对象导出到 MATLAB 基础工作区中的变量，请在运行 codegen 命令时在变量名称中包含 -reportinfo 选项。在此示例中，您将代码生成报告信息导出为变量 info。

codegen -c dijkstra -args {A, p} -reportinfo info
Code generation successful.

计算代码行数

loc 函数将报告信息对象作为输入，并返回两个输出，分别包含源代码和生成代码中的行数。此函数在计算代码行数时排除空行和包括注释的行。

type loc
% LOC Calculate total lines of source and generated code in a codegen run
%
% [i, o] = loc(r) 
% Takes a report information object 'r' as input, and produces two
% outputs - 'i' and 'o' containing the total lines of code in the source
% MATLAB files and generated files respectively.

% Copyright 2018 The MathWorks, Inc.
function [i, o] = loc(r)
    narginchk(1,1);

    % Assert that input is a report information object.
    assert(isa(r, 'coder.ReportInfo'), 'Input must be of type coder.ReportInfo');

    % Fetch source and generated files from the report information object.
    sourceFiles = r.InputFiles;
    generatedFiles = r.GeneratedFiles;
    
    % Count lines of code in source and generated files. Blank lines, and
    % comments are not counted.
    i = countLines(sourceFiles, true);
    o = countLines(generatedFiles, false);
end

function count = countLines(files, isSource)
    count = 0;
    for i=1:numel(files)
        f = files(i);
        if isprop(f, 'Text')
            lines = splitlines(f.Text);
            for j=1:numel(lines)
                line = strtrim(lines{j});
                if ~isempty(line) && ~isComment(line, isSource)
                    count = count + 1;
                end
            end
            clear isComment; % clear persistent variables
        end
    end
end

function result = isComment(line, isSource)
    persistent inBlockComment;
    if isempty(inBlockComment)
        inBlockComment = false;
    end
    if isSource
        result = (startsWith(line, "%") || inBlockComment);
        if line == "%{" || line == "%}"
            inBlockComment = (line ~= "%}");
        end
    else
        result = (startsWith(line, "/") || inBlockComment);
        if startsWith(line, "/*") || endsWith(line, "*/")
            inBlockComment = ~endsWith(line, "*/");
        end
    end
end

以报告信息对象 info 作为输入来调用 loc。显示源文件和生成文件中的代码行数。

info = evalin('base', 'info');
[nLocIn, nLocOut] = loc(info);
fprintf('Lines of code in source MATLAB file(s): %d', nLocIn);
Lines of code in source MATLAB file(s): 29

fprintf('Lines of code in generated file(s): %d', nLocOut);
Lines of code in generated file(s): 3024

另请参阅

主题