我正在编写一个java程序来获取每个月的降雨量。它工作得很好,但我只需要知道如何获得一个月的指数 - 例如,有一个输出声明:降雨量最少的月份是1英寸,1.6英寸。我怎样得到'1',这是最低月份的指数?我可以得到实际最低的降雨量数字,但不是指数。
我已经尝试了几个月[n-1],但是我仍然收到错误“非静态变量月份无法从静态上下文中引用”。
任何帮助都会很棒。感谢。
//编辑
这是代码。我试着玩静态,但这只是给了我更多的错误?因此,底部的月份[n]部分是我被困住的地方。
import java.util.*;
public class Rainfall {
Scanner in=new Scanner(System.in);
int month=12;
double total=0;
double average;
double months[];
public Rainfall()
{
months=new double[12];
}
public void setMonths()
{
for(int n=1; n<=month; n++ )
{
System.out.print("Enter the rainfall (in inches) for month #"+n+": ");
months[n-1] = in.nextDouble();
//Input Validation - Cannot accept a negative number
while (months[n-1] < 0)
{
System.out.print("Rainfall must be at least 0. Please enter a new value.");
months[n-1] = in.nextDouble();
}
}
}
public double getTotalRainFall()
{
total = 0;
for(int i=0; i<12;i++)
{
total=total+months[i];
}
return total;
}
public double getAverageRainFall()
{
average = total/12;
return average;
}
public double getHighestMonth()
{
double highest=0;
for ( int i = 0; i < 12; i++)
{
if ( months[i] > highest)
{
highest = months[i] ;
}
}
return highest;
}
public double getLowestMonth()
{
double lowest = Double.MAX_VALUE;
for ( int n = 0; n < month; n++)
{
if (months[n] < lowest )
{
lowest = months[n];
}
}
return lowest;
}
public static void main(String[]args)
{
Rainfall r =new Rainfall();
r.setMonths();
System.out.println("The total rainfall for this year is " + r.getTotalRainFall());
System.out.println("The average rainfall for this year is " + r.getAverageRainFall());
System.out.println("The month with the highest amount of rain is " + months[n] + "with" + r.getHighestMonth() "inches");
System.out.println("The month with the lowest amount of rain is " + months[n] "with" + r.getLowestMonth() "inches");
}
///编辑#2 - 好的,所以上面的代码在每个月获取用户输入时都有效。现在我正在尝试设置数组thisYear中的值(即删除用户输入)。计算不再有效。我做错了什么?
package Rainfall;
public class Rainfall {
int month = 12;
double total = 0;
double average;
double getRainAt[];
public Rainfall() {
getRainAt = new double[12];
}
double getTotalRain() {
for (int i = 0; i < 12; i++) {
total = total + getRainAt[i];
}
return total;
}
double getAverageRain() {
average = total / 12;
return average;
}
int getHighestMonth() {
int high = 0;
for (int i = 0; i < 12; i++) {
if (getRainAt[i] > getRainAt[high]) {
high = i;
}
}
return high;
}
int getLowestMonth() {
int low = 0;
for (int i = 0; i < 12; i++) {
if (getRainAt[i] < getRainAt[low]) {
low = i;
}
}
return low;
}
public static void main(String[] args) {
// Create an array of rainfall figures.
double thisYear[] = {1.6, 2.1, 1.7, 3.5, 2.6, 3.7,
3.9, 2.6, 2.9, 4.3, 2.4, 3.7 };
int high; // The high month
int low; // The low month
// Create a RainFall object initialized with the figures
// stored in the thisYear array.
Rainfall r = new Rainfall(thisYear);
// Display the statistics.
System.out.println("The total rainfall for this year is " +
r.getTotalRain());
System.out.println("The average rainfall for this year is " +
r.getAverageRain());
high = r.getHighestMonth();
System.out.println("The month with the highest amount of rain " +
"is " + (high+1) + " with " + r.getRainAt(high) +
" inches.");
low = r.getLowestMonth();
System.out.println("The month with the lowest amount of rain " +
"is " + (low+1) + " with " + r.getRainAt(low) +
" inches.");
}
}
答案 0 :(得分:1)
你可以这样使用。
double getIndex(double value) {
Arrays.asList(getRainAt).indexOf(value);
}
答案 1 :(得分:0)
一种解决方案,使用Map
和枚举数月:
package com.stackoverflow.so17289710;
import java.util.*;
public class Rainfall {
public static enum Month {
JANUARY, FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER, OCTOBER, NOVEMBER, DECEMBER;
}
private final Map<Month, Double> months;
public Rainfall()
{
this.months = new TreeMap<Month, Double>(); // treeMap for order
for (final Month month : Month.values()) {
this.months.put(month, 0.0);
}
}
public void setUpMonths()
{
final Scanner in = new Scanner(System.in);
try {
for (final Map.Entry<Month, Double> entry : this.months.entrySet()) {
do {
System.out.print("Enter the rainfall (in inches) for " + entry.getKey().name() + " (>=0): ");
entry.setValue(in.nextDouble()); // TODO validation (handle text input, ...)
// Input Validation - Cannot accept a negative number
} while (Math.signum(entry.getValue()) == -1);
}
} finally {
in.close();
}
}
public double computeTotalRainFall()
{
double total = 0.0;
for (final Map.Entry<Month, Double> entry : this.months.entrySet()) {
total += entry.getValue();
}
return total;
}
public double computeAverageRainFall()
{
return this.computeTotalRainFall() / (1.0 * this.months.size());
}
public Map.Entry<Month, Double> computeHighestMonth()
{
Map.Entry<Month, Double> highest = null;
for (final Map.Entry<Month, Double> entry : this.months.entrySet()) {
if (highest == null || highest.getValue() < entry.getValue()) {
highest = entry;
}
}
return highest;
}
public Map.Entry<Month, Double> computeLowestMonth()
{
Map.Entry<Month, Double> lowest = null;
for (final Map.Entry<Month, Double> entry : this.months.entrySet()) {
if (lowest == null || lowest.getValue() > entry.getValue()) {
lowest = entry;
}
}
return lowest;
}
}
package com.stackoverflow.so17289710;
import com.stackoverflow.so17289710.Rainfall.Month;
import java.util.Map.Entry;
public class App {
public static void main(final String[] args)
{
// TODO: formatting of doubles
final Rainfall r =new Rainfall();
r.setUpMonths();
System.out.println("The total rainfall for this year is " + r.computeTotalRainFall());
System.out.println("The average rainfall for this year is " + r.computeAverageRainFall());
final Entry<Month, Double> lowestMonth = r.computeLowestMonth();
System.out.println("The month with the highest amount of rain is " + lowestMonth.getKey() + " with " + lowestMonth.getValue() + " inches");
final Entry<Month, Double> highestMonth = r.computeHighestMonth();
System.out.println("The month with the lowest amount of rain is " + highestMonth.getKey() + " with " + highestMonth.getValue() + " inches");
}
}