函数 contour 在 Scilab 中的输出与在 MATLAB 中的输出不同？

Question

我正在尝试将此 Matlab 代码转换为 Scilab，但我遇到了一些问题。

clear all; clc;
c0  =  0.8;
c1  =  1.3;
c11 = -6.1;
c12 = -0.6;
c2  =  1.7;
c22 = -1.7;
g = 0.05; 
d = 0.01; 
x1 = -9; 
x2 = 8; 
k = 1;  
kmax = 100; 
x1trace = [x1]; 
x2trace = [x2]; 
i = 2;

while k < kmax 
    gr1 = c1 + c12*x2 + 2*c11*x1; 
    x1 = x1 + g*gr1
    x1trace(i) = x1; 
    x2trace(i) = x2;
    i = i + 1; 
    gr2 = c2 + c12*x1 + 2*c22*x2; 
    x2 = x2 + g*gr2
    x1trace(i) = x1; 
    x2trace(i) = x2; 
    i = i + 1; 
    if sqrt(gr1^2 + gr2^2) <= d; 
        break; 
    end
    k = k + 1; 
end

x = -10:0.1:10; 
y = -10:0.1:10; 
[X, Y] = meshgrid(x, y); 
Z = c0 + c1*X + c2*Y + c12*X.*Y + c11*X.^2 + c22*Y.^2; 
[C, h] = contour(X, Y, Z); 
clabel(C, h); 

hold on;
plot(x1trace, x2trace, '-'); 
text(x1trace(1) + 0.2, x2trace(1) + 0.5, 'M0'); 
text(x1 + 2, x2, ...
strvcat(['x1 = ' (num2str(x1))], ...
        ['x2 = ' (num2str(x2))], ...
        ['k = '  (num2str(k))])); 
hold off;

我收到此行的错误：

[C, h] = contour(X, Y, Z);
Wrong number of output arguments.

我应该更改什么来修复它？代码中是否还有其他错误？

Answer 1

您应该具有与以下 Scilab 代码大致相同的渲染效果。 Scilab 的 contour 需要（在第 4 个参数中）水平曲线的数量或值本身。此外，您应该使用 ndgrid 而不是 meshgrid:

clear clc;
c0  =  0.8;
c1  =  1.3;
c11 = -6.1;
c12 = -0.6;
c2  =  1.7;
c22 = -1.7;
g = 0.05; 
d = 0.01; 
x1 = -9; 
x2 = 8; 
k = 1;  
kmax = 100; 
x1trace = [x1]; 
x2trace = [x2]; 
i = 2;

while k < kmax 
    gr1 = c1 + c12*x2 + 2*c11*x1; 
    x1 = x1 + g*gr1
    x1trace(i) = x1; 
    x2trace(i) = x2;
    i = i + 1; 
    gr2 = c2 + c12*x1 + 2*c22*x2; 
    x2 = x2 + g*gr2
    x1trace(i) = x1; 
    x2trace(i) = x2; 
    i = i + 1; 
    if sqrt(gr1^2 + gr2^2) <= d; 
        break; 
    end
    k = k + 1; 
end

x = -10:0.1:10; 
y = -10:0.1:10; 
[X, Y] = ndgrid(x, y); 
Z = c0 + c1*X + c2*Y + c12*X.*Y + c11*X.^2 + c22*Y.^2; 

clf
gcf.color_map=parulacolormap(8)($:-1:1,:)
contour(x, y, Z,0:-100:-700); 

plot(x1trace, x2trace, '-'); 
xstring(x1trace(1) + 0.2, x2trace(1) + 0.5, 'M0'); 
xstring(x1 + 2, x2, ...
['x1 = '+string(x1)
 'x2 = '+string(x2)
 'k = '+string(k)]);

函数 contour 在 Scilab 中的输出与在 MATLAB 中的输出不同？

The function contour has different outputs in Scilab than in MATLAB?

matlab

scilab