为什么MATLAB自动将变量转换为矩阵？

Question

以下代码生成（3x1）矩阵的利润变量。如何从利润函数中获得一个答案（值）？

    public class Expression {

    private int idExpression;
    private String expressionFrancais;
    private String expressionAnglais;

    public Expression(int idExpression, String expressionFrancais, String expressionAnglais) {
        this.idExpression = idExpression;
        this.expressionFrancais = expressionFrancais;
        this.expressionAnglais = expressionAnglais;
    }

    public int getIdExpression() {

        return idExpression;
    }

    public void setIdExpression(int idExpression) {
        this.idExpression = idExpression;
    }

    public String getExpressionFrancais() {
        return expressionFrancais;
    }

    public void setExpressionFrancais(String expressionFrancais) {
        this.expressionFrancais = expressionFrancais;
    }

    public String getExpressionAnglais() {
        return expressionAnglais;
    }

    public void setExpressionAnglais(String expressionAnglais) {
        this.expressionAnglais = expressionAnglais;
    }
}

上面的代码输出以下答案：

for j =1:56
      b = 20  ;
      c1 =  30 ;
      Qt = 100;

      Profit =  (- (Qt^2*(b - c1))/(b + c1)^3 - (Qt*c1*l1)/(b + c1)^2 - (2*Qt^2*b*c1*l2)/(b + c1)^3);

end for 

Answer 1

问题已解决。

程序中的l2和l1是3x1矩阵。这就是为什么我得到3x1作为答案的原因。