我在一个文本文件中有 1,000 行数据，我希望每一行都是自己的 float []。
1,1,1,1,1,1
2,2,2,2,2,2
3,3,3,3,3,3
会导致：
float[0] = {1,1,1,1,1,1}
float[1] = {2,2,2,2,2,2}
float[2] = {3,3,3,3,3,3}
这可能吗？我只能找到将整个文件加载到数组中的示例。我尝试对所有数组进行硬编码，但超出了 ~65,000 的字节字符限制
【问题讨论】：
使用 .split("\n") 遍历文件的行分隔内容，然后将每个结果转换为浮点数组。以下是如何将字符串转换为浮点数 => http://www.devdaily.com/java/edu/qanda/pjqa00013.shtml
【讨论】：
使用LineIterator 读取每一行而不加载整个文件
对于每一行，使用正则表达式提取像 (\d\.)+ 这样的数字，并使用像 find()这样的方法找到的匹配项进行迭代> 和 group()
【讨论】：
尝试以下方法：
// this list will store all the created arrays
List<float[]> arrays = new ArrayList<float[]>();
// use a BufferedReader to get the handy readLine() function
BufferedReader reader = new BufferedReader(new FileReader("myfile.txt"));
// this reads in all the lines. If you only want the first thousand, just
// replace these loop conditions with a regular counter variable
for (String line = reader.readLine(); line != null; line = reader.readLine()) {
String[] floatStrings = line.split(",");
float[] floats = new float[floatStrings.length];
for (int i = 0; i < floats.length; ++i) {
floats[i] = Float.parseFloat(floatStrings[i]);
}
arrays.add(floats);
}
请注意，我没有添加任何异常处理（例如 readLine()，抛出 IOException）。
【讨论】：
<body>
<pre>
import java.io.FileReader;
public class Check {
public static void main(String[] args) {
readingfile();
}
public static void readingfile() {
try {
FileReader read = new FileReader("D:\\JavaWkspace\\numbers.txt");
int index;
String nums1 = "";
while ((index = read.read()) != -1) {
if (((char) index) != '\n') {
nums1 += String.valueOf((char) index);
}
}
System.out.println("Problem statement: Print out the greatest number on each line:\n" + nums1);
String f = nums1.substring(0, 14);
String s = nums1.substring(15, 29);
String t = nums1.substring(30);
String[] fs = f.split(",");
int size = fs.length;
int[] arr = new int[size];
for (int i = 0; i < size; i++) {
arr[i] = Integer.parseInt(fs[i]);
}
int max = arr[0];
for (int i = 0; i < arr.length; i++) {
if (max < arr[i]) {
max = arr[i];
}
}
System.out.println("\nGreatest number in the first line is:" + (max));
String[] sstr = s.split(",");
int size2 = sstr.length;
int[] arr2 = new int[size2];
for (int i = 0; i < size2; i++) {
arr2[i] = Integer.parseInt(sstr[i]);
}
int max2 = arr2[0];
for (int i = 0; i < arr2.length; i++) {
if (max2 < arr2[i]) {
max2 = arr2[i];
}
}
System.out.println("\nGreatest number in the second line is:" + (max2));
String[] str3 = t.split(",");
int size3 = str3.length;
int[] arr3 = new int[size3];
for (int i = 0; i < size3; i++) {
arr3[i] = Integer.parseInt(str3[i]);
}
int max3 = arr3[0];
for (int i = 0; i < arr3.length; i++) {
if (max3 < arr3[i]) {
max3 = arr3[i];
}
}
System.out.println("\nGreatest number in the third line is:" + (max3));
read.close();
} catch (Exception e) {
System.out.println(e);
}
}
}
</pre>
</body>【讨论】：