【发布时间】:2016-08-18 19:48:18
【问题描述】:
使用下面的代码,当输出到 GUI 中的标签时,变量(双精度)dAvgRun1、dAvgRun2(因此变量 dBest)返回为 NaN。
我在代码中做错了什么使我的双打成为 NaN?
double [][] daRun = new double[2][7];
//Sets Athlete Name and Nationality labels to selected athlete in JList
jLabel_Athlete.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).sName);
jLabel_Country.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).sCountry);
//Returns all scores for selected athlete
jTextField_Run1_0.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[0]);
jTextField_Run1_1.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[1]);
jTextField_Run1_2.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[2]);
jTextField_Run1_3.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[3]);
jTextField_Run1_4.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[4]);
jTextField_Run1_5.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[5]);
jTextField_Run1_6.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun1[6]);
jTextField_Run2_0.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[0]);
jTextField_Run2_1.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[1]);
jTextField_Run2_2.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[2]);
jTextField_Run2_3.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[3]);
jTextField_Run2_4.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[4]);
jTextField_Run2_5.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[5]);
jTextField_Run2_6.setText(vecAthlete.get(jList_Athlete.getSelectedIndex()).saTempRun2[6]);
//Parse all scores from string to double
daRun[0][0] = Double.parseDouble(jTextField_Run1_0.getText());
daRun[0][1] = Double.parseDouble(jTextField_Run1_1.getText());
daRun[0][2] = Double.parseDouble(jTextField_Run1_2.getText());
daRun[0][3] = Double.parseDouble(jTextField_Run1_3.getText());
daRun[0][4] = Double.parseDouble(jTextField_Run1_4.getText());
daRun[0][5] = Double.parseDouble(jTextField_Run1_5.getText());
daRun[0][6] = Double.parseDouble(jTextField_Run1_6.getText());
daRun[1][0] = Double.parseDouble(jTextField_Run2_0.getText());
daRun[1][1] = Double.parseDouble(jTextField_Run2_1.getText());
daRun[1][2] = Double.parseDouble(jTextField_Run2_2.getText());
daRun[1][3] = Double.parseDouble(jTextField_Run2_3.getText());
daRun[1][4] = Double.parseDouble(jTextField_Run2_4.getText());
daRun[1][5] = Double.parseDouble(jTextField_Run2_5.getText());
daRun[1][6] = Double.parseDouble(jTextField_Run2_6.getText());
//Finds maximum and minimum scores for both runs
int z;
double dMinScoreRun1 = 10, dMaxScoreRun1 = 0;
double dMinScoreRun2 = 10, dMaxScoreRun2 = 0;
for (z=0; z<daRun.length; z++)
{
if (daRun[0][z] > dMaxScoreRun1)
{dMaxScoreRun1 = daRun[0][z];}
if (daRun[0][z] < dMinScoreRun1)
{dMinScoreRun1 = daRun[0][z];}
if (daRun[1][z] > dMaxScoreRun2)
{dMaxScoreRun2 = daRun[1][z];}
if (daRun[1][z] < dMinScoreRun2)
{dMinScoreRun2 = daRun[1][z];}
}
//Calculates average scores
double dTotalRun1 = 0, dTotalRun2 = 0;
double dAvgRun1 = 0, dAvgRun2 = 0;
//Run 1
for (z=0; z<daRun.length; z++)
{
if(daRun[0][z] == dMaxScoreRun1 || daRun[0][z] == dMinScoreRun1)
continue;
dTotalRun1 += daRun[0][z];
}
dAvgRun1 = dTotalRun1 / (daRun.length-2);
//Run 2
for (z=0; z<daRun.length; z++)
{
if(daRun[1][z] == dMaxScoreRun2 || daRun[1][z] == dMinScoreRun2)
continue;
dTotalRun2 += daRun[1][z];
}
dAvgRun2 = dTotalRun2 / (daRun.length-2);
//Displays averages for both runs
jLabel_Average1.setText(Double.toString(dAvgRun1));
jLabel_Average2.setText(Double.toString(dAvgRun2));
//Compare both scores to find the best score.
double dBest = dAvgRun1;
if (dAvgRun2 > dAvgRun1)
{
dBest = dAvgRun2;
}
//Sets text of lblBestScore to the highest of the two scores
jLabel_Best.setText(Double.toString(dBest));
【问题讨论】:
-
看起来你的循环真的很小。我会在
dAvgRun1的定义之后的第一个循环的开头放置一个断点,然后调试应用程序。但要获得 NaN,您可以将 0.0 除以 0.0。 -
关于代码质量的旁注:您不仅可以构建双精度或整数数组。您还可以构建文本字段的数组(或更好的列表)。你知道,使用 12 个不同名称的文本字段来获取将存储在数组中的值有点疯狂。您重复代码 12 次,可以通过使用文本字段数组来大大压缩。
-
@Jägermeister 感谢您的提示。我试图让类似的东西与这个程序的前一个迭代一起工作,但我无法理解它。下次我需要做这样重复的事情时,我一定会记住这一点。
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@RThomP 我只能推荐:永远不要重复代码。一旦你看到自己输入了你刚刚输入的东西;停在那里;并专注于寻找不需要重复代码的解决方案。