Example usage for java.lang Math log

Introduction

In this page you can find the example usage for java.lang Math log.

Prototype

@HotSpotIntrinsicCandidate
public static double log(double a)

Source Link

Document

Returns the natural logarithm (base e) of a double value.

Usage

From source file:Main.java

public static File downSample(Context context, Uri uri) throws Exception {
    Bitmap b = null;/*w ww  . jav  a 2 s  .  c  o m*/

    //Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;

    int scale = 1;
    if (o.outHeight > MAX_SIZE || o.outWidth > MAX_SIZE) {
        scale = (int) Math.pow(2, (int) Math
                .round(Math.log(MAX_SIZE / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5)));
    }

    //Decode with inSampleSize
    BitmapFactory.Options o2 = new BitmapFactory.Options();
    o2.inSampleSize = scale;
    InputStream is = context.getContentResolver().openInputStream(uri);
    b = BitmapFactory.decodeStream(is, null, o2);
    is.close();

    File outputDir = context.getCacheDir();
    File outputFile = File.createTempFile("avatar", ".jpg", outputDir);
    FileOutputStream fos = new FileOutputStream(outputFile);
    b.compress(Bitmap.CompressFormat.JPEG, 80, fos);
    fos.close();

    return outputFile;
}

From source file:Main.java

/**
 * Returns the lat/lng as an "Offset Normalized Mercator" pixel coordinate,
 * this is a coordinate that runs from 0..1 in latitude and longitude with 0,0 being
 * top left. Normalizing means that this routine can be used at any zoom level and
 * then multiplied by a power of two to get actual pixel coordinates.
 *//*  w w w.ja  va 2  s  . c  om*/
public static Point2D toNormalisedPixelCoords(double lat, double lng) {
    // first convert to Mercator projection
    // first convert the lat lon to mercator coordintes.
    if (lng > 180) {
        lng -= 360;
    }

    lng /= 360;
    lng += 0.5;

    lat = 0.5 - ((Math.log(Math.tan((Math.PI / 4) + ((0.5 * Math.PI * lat) / 180))) / Math.PI) / 2.0);

    return new Point2D.Double(lng, lat);
}

From source file:Main.java

public static Bitmap decodeFile(File f, int maxSize) {
    Bitmap b = null;//from w w  w .  j  a v a 2  s  .  c  om
    try {
        //Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;

        FileInputStream fis = new FileInputStream(f);
        BitmapFactory.decodeStream(fis, null, o);
        fis.close();

        int scale = 1;
        if (o.outHeight > maxSize || o.outWidth > maxSize) {
            scale = (int) Math.pow(2, (int) Math
                    .round(Math.log(maxSize / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5)));
        }

        //Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        fis = new FileInputStream(f);
        b = BitmapFactory.decodeStream(fis, null, o2);
        fis.close();
    } catch (IOException e) {
    }
    return b;
}

From source file:Main.java

static public final float log(float a) {
    return (float) Math.log(a);
}

From source file:Main.java

public static Bitmap decodeFileFromDrawable(int id, int maxSize, Context context) {
    Bitmap b = null;//w w  w .jav a 2 s . c  o m
    try {
        // Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;

        InputStream inputStream = context.getResources().openRawResource(id);
        BitmapFactory.decodeStream(inputStream, null, o);
        inputStream.close();

        int scale = 1;
        if (o.outHeight > maxSize || o.outWidth > maxSize) {
            scale = (int) Math.pow(2, (int) Math
                    .round(Math.log(maxSize / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5)));
        }

        // Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        inputStream = context.getResources().openRawResource(id);
        b = BitmapFactory.decodeStream(inputStream, null, o2);
        inputStream.close();
    } catch (IOException e) {
    }
    return b;
}

From source file:Main.java

public static int getInSampleSize(double scale) {
    double log = Math.log(scale) / Math.log(2);
    double logCeil = Math.ceil(log);
    return ((int) Math.pow(2, logCeil) + 1);
}

From source file:gedi.util.math.stat.distributions.LfcDistribution.java

public static double ptol(double p) {
    return Math.log(p / (1 - p)) / Math.log(2);
}

From source file:Main.java

public static double atanh(double x) {

    return Math.log((1.0 + x) / (1.0 - x)) / 2.0;
}

From source file:Main.java

public static String ReadableByteCount(long bytes) {
    if (bytes < 1024)
        return bytes + " B";
    int exp = (int) (Math.log(bytes) / Math.log(1024));
    String pre = String.valueOf("KMGTPE".charAt(exp - 1));
    return String.format("%.1f %sB", bytes / Math.pow(1024, exp), pre);
}

From source file:Main.java

/**
 * /*from ww  w .  j a v  a2s  . co m*/
 * @param file
 */
public static void decodeFile(File file) {
    Bitmap bitmap = null;

    try {
        // Decode image size
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;

        FileInputStream fileInputStream = new FileInputStream(file);
        BitmapFactory.decodeStream(fileInputStream, null, options);
        fileInputStream.close();

        int scale = 1;

        if (options.outHeight > 500 || options.outWidth > 500) {
            scale = (int) Math.pow(2, (int) Math.round(
                    Math.log(500 / (double) Math.max(options.outHeight, options.outWidth)) / Math.log(0.5)));
        }

        // Decode with inSampleSize
        BitmapFactory.Options options2 = new BitmapFactory.Options();
        options2.inSampleSize = scale;

        fileInputStream = new FileInputStream(file);
        bitmap = BitmapFactory.decodeStream(fileInputStream, null, options2);
        fileInputStream.close();

        FileOutputStream output = new FileOutputStream(file);
        bitmap.compress(Bitmap.CompressFormat.JPEG, 90, output);

        output.flush();
        output.close();
    } catch (Exception e) {
        Log.e(TAG, e.getMessage());
    }
}