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Format code with prettier (#3375)

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acbin
2022-10-03 17:23:00 +08:00
committed by GitHub
parent 32b9b11ed5
commit e96f567bfc
464 changed files with 11483 additions and 6189 deletions
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25
src/main/java/com/thealgorithms/maths/FFT.java
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@ -143,7 +143,7 @@ public class FFT {
public Complex divide(Complex z) {
Complex temp = new Complex();
double d = z.abs() * z.abs();
d = (double)Math.round(d * 1000000000d) / 1000000000d;
d = (double) Math.round(d * 1000000000d) / 1000000000d;
temp.real = (this.real * z.real + this.img * z.img) / (d);
temp.img = (this.img * z.real - this.real * z.img) / (d);
return temp;
@ -180,12 +180,15 @@ public class FFT {
* @param inverse True if you want to find the inverse FFT.
* @return
*/
public static ArrayList<Complex> fft(ArrayList<Complex> x, boolean inverse) {
public static ArrayList<Complex> fft(
ArrayList<Complex> x,
boolean inverse
) {
/* Pad the signal with zeros if necessary */
paddingPowerOfTwo(x);
int N = x.size();
int log2N = findLog2(N);
x = fftBitReversal(N,log2N,x);
x = fftBitReversal(N, log2N, x);
int direction = inverse ? -1 : 1;
/* Main loop of the algorithm */
@ -203,12 +206,12 @@ public class FFT {
}
}
}
x = inverseFFT(N,inverse,x);
x = inverseFFT(N, inverse, x);
return x;
}
/* Find the log2(N) */
public static int findLog2(int N){
public static int findLog2(int N) {
int log2N = 0;
while ((1 << log2N) < N) {
log2N++;
@ -217,7 +220,11 @@ public class FFT {
}
/* Swap the values of the signal with bit-reversal method */
public static ArrayList<Complex> fftBitReversal(int N, int log2N, ArrayList<Complex> x){
public static ArrayList<Complex> fftBitReversal(
int N,
int log2N,
ArrayList<Complex> x
) {
int reverse;
for (int i = 0; i < N; i++) {
reverse = reverseBits(i, log2N);
@ -229,7 +236,11 @@ public class FFT {
}
/* Divide by N if we want the inverse FFT */
public static ArrayList<Complex> inverseFFT(int N, boolean inverse, ArrayList<Complex> x ){
public static ArrayList<Complex> inverseFFT(
int N,
boolean inverse,
ArrayList<Complex> x
) {
if (inverse) {
for (int i = 0; i < x.size(); i++) {
Complex z = x.get(i);