我有一个像这样的.txt文件:(它实际上更长）
5.4167707e-02 7.4330113e-02 1.3307861e-01 1.1399230e-01 9.7865982e-02 -4.5091141e-02 5.4978066e-02 1.9342541e-01 1.3783929e-01
是字符串（一行）。我需要读取文件并在计算中使用这些值。值应该像input [i]。
到目前为止，这是我的代码：
public class MainActivity extends AppCompatActivity {
AudioAnalyzer aa = new AudioAnalyzer();
BufferedReader brinput = null , brbandpass = null;
InputStream isinput = null, isbandpass = null;
InputStreamReader isrinput = null, isrbandpass = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void analyzer (View view) throws FileNotFoundException{
try {
isinput = new FileInputStream("/storage/sdcard/input.txt");
isbandpass = new FileInputStream("/storage/sdcard/bandpass.txt");
isrinput = new InputStreamReader(isinput);
isrbandpass = new InputStreamReader(isbandpass);
brinput = new BufferedReader(isrinput);
brbandpass = new BufferedReader(isrbandpass);
//reads to the end of the stream
int i;
int f;
while ((i = brinput.read()) != -1) {
f = brbandpass.read();
double input = (double)i; // int to double
double filtered = (double)f;
String working = "The filter works!";
String notworking = "Try again. The filter does not work!";
TextView t = (TextView) findViewById(R.id.textView);
if (aa.analyze(in, fil) = true) // Analyze is the methode I want to use the values for
t.setText(working);
else
t.setText(notworking);
} catch (IOException e) {
e.printStackTrace();
}
}
由于红线错误，我无法运行程序：f（“f”可能尚未初始化）已编辑我想将文本文件中的每个值从int转换为double类型
double filtered = (double)f;
并且在输入下，过滤（analyze（double []，double []）不能应用于（double，double）。已编辑如何将其转换为数组，以适应方法？
if (aa.analyze(input, filtered) = true)
被修改 这是我的分析方法：
public class AudioAnalyzer {
private IIRFilter bandpass, lowpass;
final double[] b1 = {0.0286, 0, -0.0859, 0, 0.0859, 0, -0.0286};
final double[] a1 = {-3.9320, 6.8170, -6.7455, 4.0453, -1.3889, 0.2120};
public AudioAnalyzer() {
bandpass = new IIRFilter(b1, a1);
}
public boolean analyze(double[] inputFilter, double[] outputFilter) {
int i;
boolean work;
double[] w;
double g1[] = new double[inputFilter.length];
for (i = 0; i < inputFilter.length; i++) {
double f1 = inputFilter[i];
g1[i] = outputFilter[i]-(bandpass.filter(f1));
for ( i = 0;i < g1.length; i++)
w[i] = g1[i]-outputFilter[i];
if (w[i] == 0)
work = true;
return work;
}
我的过滤器类：
public class IIRFilter {
private final double[] b;
private final double[] a;
private double[] g; //g(n) = output
private double[] f; //f(n) = input
public IIRFilter(double[] b, double[] a) {
this.a = a;
this.b = b;
g = new double[a.length];
f = new double[b.length];
Arrays.fill(g, 0.0);
Arrays.fill(f, 0.0);
}
public double filter(double f0) {
// change the values' positions in the buffer f
int s;
for (s=f.length-1;s>0; s--){
f[s] = f[s-1];
}
f[0] = f0;
//filter equation
int n;
double gt;
double ht;
ht = 0.0;
gt = 0.0;
for (n = 0; n < b.length; n++) {
ht += b[n] * f[n];
}
for (n = 0; n < a.length; n++) {
gt -= a[n] * g[n];
}
// change the values' positions in the buffer g
for ( s=g.length; s>0; s--){
g[s] = g[s-1];
}
g[0] = ht+gt;
return g[0];
}
}
答案 0 :(得分：0)
您可以尝试使用该代码
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class MainActivity extends AppCompatActivity {
AudioAnalyzer aa = new AudioAnalyzer();
TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textView = (TextView) findViewById(R.id.textView);
}
public void analyzer (View view) throws FileNotFoundException{
try {
double[] input = readFile("/storage/sdcard/input.txt");
double[] analyzed = readFile("/storage/sdcard/bandpass.txt");
isWorking(aa.analyze(input, analyzed));
catch (IOException e) {
e.printStackTrace();
}
}
private void isWorking(boolean working){
if(working)
textView.setText("The filter works!");
else
textView.setText("Try again. The filter does not work!");
}
public double[] readFile(String fname) throws FileNotFoundException {
File file = new File(fname);
Scanner scanner = new Scanner(new FileInputStream(file));
List<Double> collection = new ArrayList<Double>();
while (scanner.hasNextDouble()){
double number = scanner.nextDouble();
collection.add(number);
}
scanner.close();
return toPrimitive(collection.toArray(new Double[collection.size()]));
}
public double[] toPrimitive(Double[] array) {
if (array == null) {
return null;
} else if (array.length == 0) {
return null;
}
final double[] result = new double[array.length];
for (int i = 0; i < array.length; i++) {
result[i] = array[i].doubleValue();
}
return result;
}
}
分析仪
public class AudioAnalyzer {
private IIRFilter bandpass, lowpass;
final double[] b1 = {0.0286, 0, -0.0859, 0, 0.0859, 0, -0.0286};
final double[] a1 = {-3.9320, 6.8170, -6.7455, 4.0453, -1.3889, 0.2120};
public AudioAnalyzer() {
bandpass = new IIRFilter(b1, a1);
}
public boolean analyze(double[] inputFilter, double[] outputFilter) {
int i;
double g1[] = new double[inputFilter.length];
for (i = 0; i < inputFilter.length; i++) {
double f1 = inputFilter[i];
g1[i] = outputFilter[i]-(bandpass.filter(f1));
for (i = 0; i < g1.length; i++){
if (( g1[i]-outputFilter[i] != 0))
return false;
}
return true;
}
}