private void button_StartTesting_Click(object sender, EventArgs e)
 {
     result = Stat.HypothesisTesting2(MainForm.MainDT, comboBox_Cols.Text, comboBox_Cols2.Text,
                                      comboBox_Statistics.Text, comboBox_Operation.Text, comboBox_Tail.Text,
                                      Convert.ToDouble(comboBox_Significance.Text), Convert.ToDouble(textBox_NullHypothesis.Text), comboBox_proportion.Text, Convert.ToDouble(textBox_comapre.Text));
     MainForm.S.richTextBox1.AppendText(result);
     MainForm.S.richTextBox1.Select();                                      //让RichTextBox获得焦点
     MainForm.S.richTextBox1.Select(MainForm.S.richTextBox1.TextLength, 0); //将插入符号置于文本结束处
     MainForm.S.richTextBox1.ScrollToCaret();
 }