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style: enable LocalVariableName in CheckStyle (#5191)

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* style: enable LocalVariableName in checkstyle

* Removed minor bug

* Resolved Method Name Bug

* Changed names according to suggestions
This commit is contained in:
S. Utkarsh
2024-05-28 23:59:28 +05:30
committed by GitHub
parent 81cb09b1f8
commit 25d711c5d8
45 changed files with 418 additions and 417 deletions
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24
src/main/java/com/thealgorithms/maths/FFTBluestein.java
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@ -26,8 +26,8 @@ public final class FFTBluestein {
* @param inverse True if you want to find the inverse FFT.
*/
public static void fftBluestein(ArrayList<FFT.Complex> x, boolean inverse) {
int N = x.size();
int bnSize = 2 * N - 1;
int n = x.size();
int bnSize = 2 * n - 1;
int direction = inverse ? -1 : 1;
ArrayList<FFT.Complex> an = new ArrayList<>();
ArrayList<FFT.Complex> bn = new ArrayList<>();
@ -38,32 +38,32 @@ public final class FFTBluestein {
bn.add(new FFT.Complex());
}
for (int i = 0; i < N; i++) {
double angle = (i - N + 1) * (i - N + 1) * Math.PI / N * direction;
for (int i = 0; i < n; i++) {
double angle = (i - n + 1) * (i - n + 1) * Math.PI / n * direction;
bn.set(i, new FFT.Complex(Math.cos(angle), Math.sin(angle)));
bn.set(bnSize - i - 1, new FFT.Complex(Math.cos(angle), Math.sin(angle)));
}
/* Initialization of the a(n) sequence */
for (int i = 0; i < N; i++) {
double angle = -i * i * Math.PI / N * direction;
for (int i = 0; i < n; i++) {
double angle = -i * i * Math.PI / n * direction;
an.add(x.get(i).multiply(new FFT.Complex(Math.cos(angle), Math.sin(angle))));
}
ArrayList<FFT.Complex> convolution = ConvolutionFFT.convolutionFFT(an, bn);
/* The final multiplication of the convolution with the b*(k) factor */
for (int i = 0; i < N; i++) {
double angle = -1 * i * i * Math.PI / N * direction;
for (int i = 0; i < n; i++) {
double angle = -1 * i * i * Math.PI / n * direction;
FFT.Complex bk = new FFT.Complex(Math.cos(angle), Math.sin(angle));
x.set(i, bk.multiply(convolution.get(i + N - 1)));
x.set(i, bk.multiply(convolution.get(i + n - 1)));
}
/* Divide by N if we want the inverse FFT */
/* Divide by n if we want the inverse FFT */
if (inverse) {
for (int i = 0; i < N; i++) {
for (int i = 0; i < n; i++) {
FFT.Complex z = x.get(i);
x.set(i, z.divide(N));
x.set(i, z.divide(n));
}
}
}