List of usage examples for java.lang Math pow
@HotSpotIntrinsicCandidate public static double pow(double a, double b)
From source file:Main.java
/** * Fills the array with random doubles. Values will be between min (inclusive) and * max (inclusive)./*from w w w. ja v a 2 s . co m*/ */ public static void genRandomDoubles(long seed, double min, double max, double array[], boolean includeExtremes) { Random r = new Random(seed); int minExponent = Math.min(Math.getExponent(min), 0); int maxExponent = Math.max(Math.getExponent(max), 0); if (minExponent < -6 || maxExponent > 6) { // Use an exponential distribution int exponentDiff = maxExponent - minExponent; for (int i = 0; i < array.length; i++) { double mantissa = r.nextDouble(); int exponent = minExponent + r.nextInt(maxExponent - minExponent); int sign = (min >= 0) ? 1 : 1 - r.nextInt(2) * 2; // -1 or 1 double rand = sign * mantissa * Math.pow(2.0, exponent); if (rand < min || rand > max) { continue; } array[i] = rand; } } else { // Use a linear distribution for (int i = 0; i < array.length; i++) { double rand = r.nextDouble(); array[i] = min + rand * (max - min); } } // Seed a few special numbers we want to be sure to test. for (int i = 0; i < sInterestingDoubles.length; i++) { double d = sInterestingDoubles[i]; if (min <= d && d <= max) { array[r.nextInt(array.length)] = d; } } array[r.nextInt(array.length)] = min; array[r.nextInt(array.length)] = max; if (includeExtremes) { array[r.nextInt(array.length)] = Double.NaN; array[r.nextInt(array.length)] = Double.POSITIVE_INFINITY; array[r.nextInt(array.length)] = Double.NEGATIVE_INFINITY; array[r.nextInt(array.length)] = Double.MIN_VALUE; array[r.nextInt(array.length)] = Double.MIN_NORMAL; array[r.nextInt(array.length)] = Double.MAX_VALUE; array[r.nextInt(array.length)] = -Double.MIN_VALUE; array[r.nextInt(array.length)] = -Double.MIN_NORMAL; array[r.nextInt(array.length)] = -Double.MAX_VALUE; } }
From source file:Main.java
public static void getDisplayDpi(Context ctx) { DisplayMetrics dm = new DisplayMetrics(); WindowManager wm = (WindowManager) ctx.getSystemService(Context.WINDOW_SERVICE); wm.getDefaultDisplay().getMetrics(dm); double x = Math.pow(dm.widthPixels / dm.xdpi, 2); double y = Math.pow(dm.heightPixels / dm.ydpi, 2); double screenInches = Math.sqrt(x + y); int screenInch = (int) Math.round(screenInches); Log.d("screeninch", String.valueOf(screenInch)); int dapi = dm.densityDpi; Log.d("dapi", String.valueOf(dapi)); try {/*from w ww .j a v a2s . c o m*/ switch (dm.densityDpi) { case DisplayMetrics.DENSITY_LOW: UI_DENSITY = 120; if (screenInch <= 7) { UI_SIZE = 4; } else { UI_SIZE = 10; } break; case DisplayMetrics.DENSITY_MEDIUM: UI_DENSITY = 160; if (screenInch <= 7) { UI_SIZE = 4; } else { UI_SIZE = 10; } break; case DisplayMetrics.DENSITY_HIGH: UI_DENSITY = 240; if (screenInch <= 7) { UI_SIZE = 4; } else { UI_SIZE = 10; } break; default: break; } } catch (Exception e) { // Caught exception here } }
From source file:ChartThread.java
public ChartThread(IEvaluableEnTiempo evaluable, ChartPanel panel) { this.evaluable = evaluable; this.panel = panel; this.frames = 225; this.time = 150; frameActual = 0;/*from w w w .j a v a 2 s .c o m*/ unidad = evaluarUnidad(); if (unidad >= Math.pow(10, 11)) this.frames = 1000; }
From source file:Main.java
public static int itoa(int iSrc, byte[] buffer, int offset) { int positionalNumber = getPositionalNumber(iSrc); int length = positionalNumber; int i = offset; while (positionalNumber > 0) { int jesu = (int) Math.pow(10, positionalNumber - 1); int quotiont = iSrc / jesu; buffer[i] = (byte) (quotiont + '0'); int remainder = iSrc % jesu; positionalNumber--;//www.j a v a2s. c o m i++; iSrc = remainder; } return length; }
From source file:Main.java
/** * Returns the closest power-of-two number less than or equal to x. * * @param x input value//from w ww . j a v a 2 s. co m * * @return the closest power-of-two number less then or equal to x */ public static int prevPow2(int x) { if (x < 1) { throw new IllegalArgumentException("x must be greater or equal 1"); } return (int) Math.pow(2, Math.floor(Math.log(x) / Math.log(2))); }
From source file:Main.java
/** * Creates an approximated cubic gradient using a multi-stop linear gradient. See * <a href="https://plus.google.com/+RomanNurik/posts/2QvHVFWrHZf">this post</a> for more * details.//from w w w . ja va 2s . c o m */ public static Drawable makeCubicGradientScrimDrawable(int baseColor, int numStops, int gravity) { numStops = Math.max(numStops, 2); PaintDrawable paintDrawable = new PaintDrawable(); paintDrawable.setShape(new RectShape()); final int[] stopColors = new int[numStops]; int red = Color.red(baseColor); int green = Color.green(baseColor); int blue = Color.blue(baseColor); int alpha = Color.alpha(baseColor); for (int i = 0; i < numStops; i++) { float x = i * 1f / (numStops - 1); float opacity = constrain(0, 1, (float) Math.pow(x, 3)); stopColors[i] = Color.argb((int) (alpha * opacity), red, green, blue); } final float x0, x1, y0, y1; switch (gravity & Gravity.HORIZONTAL_GRAVITY_MASK) { case Gravity.START: x0 = 1; x1 = 0; break; case Gravity.END: x0 = 0; x1 = 1; break; default: x0 = 0; x1 = 0; break; } switch (gravity & Gravity.VERTICAL_GRAVITY_MASK) { case Gravity.TOP: y0 = 1; y1 = 0; break; case Gravity.BOTTOM: y0 = 0; y1 = 1; break; default: y0 = 0; y1 = 0; break; } paintDrawable.setShaderFactory(new ShapeDrawable.ShaderFactory() { @Override public Shader resize(int width, int height) { return new LinearGradient(width * x0, height * y0, width * x1, height * y1, stopColors, null, Shader.TileMode.CLAMP); } }); return paintDrawable; }
From source file:StringUtils.java
/** * Format a percentage for presentation to the user. * @param done the percentage to format (0.0 to 1.0) * @param digits the number of digits past the decimal point * @return a string representation of the percentage *//*from w w w .j a v a 2s . c o m*/ public static String formatPercent(double done, int digits) { DecimalFormat percentFormat = new DecimalFormat("0.00%"); double scale = Math.pow(10.0, digits + 2); double rounded = Math.floor(done * scale); percentFormat.setDecimalSeparatorAlwaysShown(false); percentFormat.setMinimumFractionDigits(digits); percentFormat.setMaximumFractionDigits(digits); return percentFormat.format(rounded / scale); }
From source file:Main.java
public static Bitmap loadMpoBitmapFromFile(File file, long offset, int maxWidth, int maxHeight) throws IOException { // First, decode the width and height of the image, so that we know how much to scale // it down when loading it into our ImageView (so we don't need to do a huge allocation). BitmapFactory.Options opts = new BitmapFactory.Options(); InputStream fs = null;/*from ww w . ja v a2 s .co m*/ try { fs = new BufferedInputStream(new FileInputStream(file)); fs.skip(offset); opts.inJustDecodeBounds = true; BitmapFactory.decodeStream(fs, null, opts); } finally { if (fs != null) { try { fs.close(); } catch (IOException e) { // don't worry } } } int scale = 1; if (opts.outHeight > maxHeight || opts.outWidth > maxWidth) { scale = (int) Math.pow(2, (int) Math .round(Math.log(maxWidth / (double) Math.max(opts.outHeight, opts.outWidth)) / Math.log(0.5))); } if ((opts.outHeight <= 0) || (opts.outWidth <= 0)) { return null; } // Decode the image for real, but now with a sampleSize. // We have to reopen the file stream, and re-skip to the correct offset, since // FileInputStream doesn't support reset(). Bitmap bmp = null; fs = null; try { fs = new BufferedInputStream(new FileInputStream(file)); fs.skip(offset); BitmapFactory.Options opts2 = new BitmapFactory.Options(); opts2.inSampleSize = scale; bmp = BitmapFactory.decodeStream(fs, null, opts2); } finally { if (fs != null) { try { fs.close(); } catch (IOException e) { // don't worry } } } return bmp; }
From source file:com.cloudera.hts.utils.math.MyFunc2.java
public double value(double t, double... parameters) { final double a = parameters[0]; final double b = parameters[1]; final double c = parameters[2]; return a * Math.pow(t, 2) + b * t + c; }
From source file:Main.java
/** * Creates an approximated cubic gradient using a multi-stop linear gradient. See * <a href="https://plus.google.com/+RomanNurik/posts/2QvHVFWrHZf">this post</a> for more * details.//w w w . j a v a 2 s . co m */ public static Drawable makeCubicGradientScrimDrawable(int baseColor, int numStops, int gravity) { // Generate a cache key by hashing together the inputs, based on the method described in the Effective Java book int cacheKeyHash = baseColor; cacheKeyHash = 31 * cacheKeyHash + numStops; cacheKeyHash = 31 * cacheKeyHash + gravity; Drawable cachedGradient = cubicGradientScrimCache.get(cacheKeyHash); if (cachedGradient != null) { return cachedGradient; } numStops = Math.max(numStops, 2); PaintDrawable paintDrawable = new PaintDrawable(); paintDrawable.setShape(new RectShape()); final int[] stopColors = new int[numStops]; int red = Color.red(baseColor); int green = Color.green(baseColor); int blue = Color.blue(baseColor); int alpha = Color.alpha(baseColor); for (int i = 0; i < numStops; i++) { float x = i * 1f / (numStops - 1); float opacity = Math.max(0, Math.min(1, (float) Math.pow(x, 3))); stopColors[i] = Color.argb((int) (alpha * opacity), red, green, blue); } final float x0, x1, y0, y1; switch (gravity & Gravity.HORIZONTAL_GRAVITY_MASK) { case Gravity.START: x0 = 1; x1 = 0; break; case Gravity.END: x0 = 0; x1 = 1; break; default: x0 = 0; x1 = 0; break; } switch (gravity & Gravity.VERTICAL_GRAVITY_MASK) { case Gravity.TOP: y0 = 1; y1 = 0; break; case Gravity.BOTTOM: y0 = 0; y1 = 1; break; default: y0 = 0; y1 = 0; break; } paintDrawable.setShaderFactory(new ShapeDrawable.ShaderFactory() { @Override public Shader resize(int width, int height) { return new LinearGradient(width * x0, height * y0, width * x1, height * y1, stopColors, null, Shader.TileMode.CLAMP); } }); cubicGradientScrimCache.put(cacheKeyHash, paintDrawable); return paintDrawable; }