AIMS/DrawGraph/Graph/ExponentScale.cs
2022-08-23 21:12:59 +08:00

405 lines
14 KiB
C#

//============================================================================
//ZedGraph Class Library - A Flexible Line Graph/Bar Graph Library in C#
//Copyright ?2005 John Champion
//
//This library is free software; you can redistribute it and/or
//modify it under the terms of the GNU Lesser General Public
//License as published by the Free Software Foundation; either
//version 2.1 of the License, or (at your option) any later version.
//
//This library is distributed in the hope that it will be useful,
//but WITHOUT ANY WARRANTY; without even the implied warranty of
//MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//Lesser General Public License for more details.
//
//You should have received a copy of the GNU Lesser General Public
//License along with this library; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//=============================================================================
using System;
using System.Collections;
using System.Text;
using System.Drawing;
using System.Runtime.Serialization;
using System.Security.Permissions;
namespace DrawGraph
{
/// <summary>
/// The ExponentScale class inherits from the <see cref="Scale" /> class, and implements
/// the features specific to <see cref="AxisType.Exponent" />.
/// </summary>
/// <remarks>
/// ExponentScale is a non-linear axis in which the values are scaled using an exponential function
/// with the <see cref="Scale.Exponent" /> property.
/// </remarks>
///
/// <author> John Champion with contributions by jackply </author>
/// <version> $Revision: 1.8 $ $Date: 2007/04/16 00:03:01 $ </version>
[Serializable]
class ExponentScale : Scale, ISerializable //, ICloneable
{
#region constructors
/// <summary>
/// Default constructor that defines the owner <see cref="Axis" />
/// (containing object) for this new object.
/// </summary>
/// <param name="owner">The owner, or containing object, of this instance</param>
public ExponentScale( Axis owner )
: base( owner )
{
}
/// <summary>
/// The Copy Constructor
/// </summary>
/// <param name="rhs">The <see cref="ExponentScale" /> object from which to copy</param>
/// <param name="owner">The <see cref="Axis" /> object that will own the
/// new instance of <see cref="ExponentScale" /></param>
public ExponentScale( Scale rhs, Axis owner )
: base( rhs, owner )
{
}
/// <summary>
/// Create a new clone of the current item, with a new owner assignment
/// </summary>
/// <param name="owner">The new <see cref="Axis" /> instance that will be
/// the owner of the new Scale</param>
/// <returns>A new <see cref="Scale" /> clone.</returns>
public override Scale Clone( Axis owner )
{
return new ExponentScale( this, owner );
}
#endregion
#region properties
public override AxisType Type
{
get { return AxisType.Exponent; }
}
#endregion
#region methods
/// <summary>
/// Setup some temporary transform values in preparation for rendering the <see cref="Axis"/>.
/// </summary>
/// <remarks>
/// This method is typically called by the parent <see cref="GraphPane"/>
/// object as part of the <see cref="GraphPane.Draw"/> method. It is also
/// called by <see cref="GraphPane.GeneralTransform(double,double,CoordType)"/> and
/// <see cref="GraphPane.ReverseTransform( PointF, out double, out double )"/>
/// methods to setup for coordinate transformations.
/// </remarks>
/// <param name="pane">
/// A reference to the <see cref="GraphPane"/> object that is the parent or
/// owner of this object.
/// </param>
/// <param name="axis">
/// The parent <see cref="Axis" /> for this <see cref="Scale" />
/// </param>
override public void SetupScaleData( GraphPane pane, Axis axis )
{
base.SetupScaleData( pane, axis );
if ( _exponent > 0 )
{
_minLinTemp = Linearize( _min );
_maxLinTemp = Linearize( _max );
}
else if ( _exponent < 0 )
{
_minLinTemp = Linearize( _max );
_maxLinTemp = Linearize( _min );
}
}
/// <summary>
/// Convert a value to its linear equivalent for this type of scale.
/// </summary>
/// <remarks>
/// The default behavior is to just return the value unchanged. However,
/// for <see cref="AxisType.Log" /> and <see cref="AxisType.Exponent" />,
/// it returns the log or power equivalent.
/// </remarks>
/// <param name="val">The value to be converted</param>
override public double Linearize( double val )
{
return SafeExp( val, _exponent );
}
/// <summary>
/// Convert a value from its linear equivalent to its actual scale value
/// for this type of scale.
/// </summary>
/// <remarks>
/// The default behavior is to just return the value unchanged. However,
/// for <see cref="AxisType.Log" /> and <see cref="AxisType.Exponent" />,
/// it returns the anti-log or inverse-power equivalent.
/// </remarks>
/// <param name="val">The value to be converted</param>
override public double DeLinearize( double val )
{
return Math.Pow( val, 1 / _exponent );
}
/// <summary>
/// Determine the value for any major tic.
/// </summary>
/// <remarks>
/// This method properly accounts for <see cref="Scale.IsLog"/>, <see cref="Scale.IsText"/>,
/// and other axis format settings.
/// </remarks>
/// <param name="baseVal">
/// The value of the first major tic (floating point double)
/// </param>
/// <param name="tic">
/// The major tic number (0 = first major tic). For log scales, this is the actual power of 10.
/// </param>
/// <returns>
/// The specified major tic value (floating point double).
/// </returns>
override internal double CalcMajorTicValue( double baseVal, double tic )
{
if ( _exponent > 0.0 )
{
//return baseVal + Math.Pow ( (double) this.majorStep * tic, exp );
//baseVal is got from CalBase..., and it is exp..
return Math.Pow( Math.Pow( baseVal, 1 / _exponent ) + _majorStep * tic, _exponent );
}
else if ( _exponent < 0.0 )
{
//baseVal is got from CalBase..., and it is exp..
return Math.Pow( Math.Pow( baseVal, 1 / _exponent ) + _majorStep * tic, _exponent );
}
return 1.0;
}
/// <summary>
/// Determine the value for any minor tic.
/// </summary>
/// <remarks>
/// This method properly accounts for <see cref="Scale.IsLog"/>, <see cref="Scale.IsText"/>,
/// and other axis format settings.
/// </remarks>
/// <param name="baseVal">
/// The value of the first major tic (floating point double). This tic value is the base
/// reference for all tics (including minor ones).
/// </param>
/// <param name="iTic">
/// The major tic number (0 = first major tic). For log scales, this is the actual power of 10.
/// </param>
/// <returns>
/// The specified minor tic value (floating point double).
/// </returns>
override internal double CalcMinorTicValue( double baseVal, int iTic )
{
return baseVal + Math.Pow( (double) _majorStep * (double) iTic, _exponent );
}
/// <summary>
/// Internal routine to determine the ordinals of the first minor tic mark
/// </summary>
/// <param name="baseVal">
/// The value of the first major tic for the axis.
/// </param>
/// <returns>
/// The ordinal position of the first minor tic, relative to the first major tic.
/// This value can be negative (e.g., -3 means the first minor tic is 3 minor step
/// increments before the first major tic.
/// </returns>
override internal int CalcMinorStart( double baseVal )
{
return (int) ( ( Math.Pow( _min, _exponent ) - baseVal ) / Math.Pow( _minorStep, _exponent ) );
}
/// <summary>
/// Select a reasonable exponential axis scale given a range of data values.
/// </summary>
/// <remarks>
/// This method only applies to <see cref="AxisType.Exponent"/> type axes, and it
/// is called by the general <see cref="Scale.PickScale"/> method. The exponential scale
/// relies on the <see cref="Scale.Exponent" /> property to set the scaling exponent. This
/// method honors the <see cref="Scale.MinAuto"/>, <see cref="Scale.MaxAuto"/>,
/// and <see cref="Scale.MajorStepAuto"/> autorange settings.
/// In the event that any of the autorange settings are false, the
/// corresponding <see cref="Scale.Min"/>, <see cref="Scale.Max"/>, or <see cref="Scale.MajorStep"/>
/// setting is explicitly honored, and the remaining autorange settings (if any) will
/// be calculated to accomodate the non-autoranged values. For log axes, the MinorStep
/// value is not used.
/// <para>On Exit:</para>
/// <para><see cref="Scale.Min"/> is set to scale minimum (if <see cref="Scale.MinAuto"/> = true)</para>
/// <para><see cref="Scale.Max"/> is set to scale maximum (if <see cref="Scale.MaxAuto"/> = true)</para>
/// <para><see cref="Scale.MajorStep"/> is set to scale step size (if <see cref="Scale.MajorStepAuto"/> = true)</para>
/// <para><see cref="Scale.Mag"/> is set to a magnitude multiplier according to the data</para>
/// <para><see cref="Scale.Format"/> is set to the display format for the values (this controls the
/// number of decimal places, whether there are thousands separators, currency types, etc.)</para>
/// </remarks>
/// <seealso cref="Scale.PickScale"/>
/// <seealso cref="AxisType.Exponent"/>
override public void PickScale( GraphPane pane, Graphics g, float scaleFactor )
{
// call the base class first
base.PickScale( pane, g, scaleFactor );
// Test for trivial condition of range = 0 and pick a suitable default
if ( _max - _min < 1.0e-20 )
{
if ( _maxAuto )
_max = _max + 0.2 * ( _max == 0 ? 1.0 : Math.Abs( _max ) );
if ( _minAuto )
_min = _min - 0.2 * ( _min == 0 ? 1.0 : Math.Abs( _min ) );
}
// This is the zero-lever test. If minVal is within the zero lever fraction
// of the data range, then use zero.
if ( _minAuto && _min > 0 &&
_min / ( _max - _min ) < Default.ZeroLever )
_min = 0;
// Repeat the zero-lever test for cases where the maxVal is less than zero
if ( _maxAuto && _max < 0 &&
Math.Abs( _max / ( _max - _min ) ) <
Default.ZeroLever )
_max = 0;
// Calculate the new step size
if ( _majorStepAuto )
{
double targetSteps = ( _ownerAxis is XAxis || _ownerAxis is X2Axis ) ?
Default.TargetXSteps : Default.TargetYSteps;
// Calculate the step size based on target steps
_majorStep = CalcStepSize( _max - _min, targetSteps );
if ( _isPreventLabelOverlap )
{
// Calculate the maximum number of labels
double maxLabels = (double) this.CalcMaxLabels( g, pane, scaleFactor );
if ( maxLabels < ( _max - _min ) / _majorStep )
_majorStep = CalcBoundedStepSize( _max - _min, maxLabels );
}
}
// Calculate the new step size
if ( _minorStepAuto )
_minorStep = CalcStepSize( _majorStep,
( _ownerAxis is XAxis || _ownerAxis is X2Axis ) ?
Default.TargetMinorXSteps : Default.TargetMinorYSteps );
// Calculate the scale minimum
if ( _minAuto )
_min = _min - MyMod( _min, _majorStep );
// Calculate the scale maximum
if ( _maxAuto )
_max = MyMod( _max, _majorStep ) == 0.0 ? _max :
_max + _majorStep - MyMod( _max, _majorStep );
// set the scale magnitude if required
if ( _magAuto )
{
// Find the optimal scale display multiple
double mag = 0;
double mag2 = 0;
if ( Math.Abs( _min ) > 1.0e-10 )
mag = Math.Floor( Math.Log10( Math.Abs( _min ) ) );
if ( Math.Abs( _max ) > 1.0e-10 )
mag2 = Math.Floor( Math.Log10( Math.Abs( _max ) ) );
if ( Math.Abs( mag2 ) > Math.Abs( mag ) )
mag = mag2;
// Do not use scale multiples for magnitudes below 4
if ( Math.Abs( mag ) <= 3 )
mag = 0;
// Use a power of 10 that is a multiple of 3 (engineering scale)
_mag = (int) ( Math.Floor( mag / 3.0 ) * 3.0 );
}
// Calculate the appropriate number of dec places to display if required
if ( _formatAuto )
{
int numDec = 0 - (int) ( Math.Floor( Math.Log10( _majorStep ) ) - _mag );
if ( numDec < 0 )
numDec = 0;
_format = "f" + numDec.ToString();
}
}
/// <summary>
/// Make a value label for an <see cref="AxisType.Exponent" /> <see cref="Axis" />.
/// </summary>
/// <param name="pane">
/// A reference to the <see cref="GraphPane"/> object that is the parent or
/// owner of this object.
/// </param>
/// <param name="index">
/// The zero-based, ordinal index of the label to be generated. For example, a value of 2 would
/// cause the third value label on the axis to be generated.
/// </param>
/// <param name="dVal">
/// The numeric value associated with the label. This value is ignored for log (<see cref="Scale.IsLog"/>)
/// and text (<see cref="Scale.IsText"/>) type axes.
/// </param>
/// <returns>The resulting value label as a <see cref="string" /></returns>
override internal string MakeLabel( GraphPane pane, int index, double dVal )
{
if ( _format == null )
_format = Scale.Default.Format;
double scaleMult = Math.Pow( (double) 10.0, _mag );
double val = Math.Pow( dVal, 1 / _exponent ) / scaleMult;
return val.ToString( _format );
}
#endregion
#region Serialization
/// <summary>
/// Current schema value that defines the version of the serialized file
/// </summary>
public const int schema2 = 10;
/// <summary>
/// Constructor for deserializing objects
/// </summary>
/// <param name="info">A <see cref="SerializationInfo"/> instance that defines the serialized data
/// </param>
/// <param name="context">A <see cref="StreamingContext"/> instance that contains the serialized data
/// </param>
protected ExponentScale( SerializationInfo info, StreamingContext context ) : base( info, context )
{
// The schema value is just a file version parameter. You can use it to make future versions
// backwards compatible as new member variables are added to classes
int sch = info.GetInt32( "schema2" );
}
/// <summary>
/// Populates a <see cref="SerializationInfo"/> instance with the data needed to serialize the target object
/// </summary>
/// <param name="info">A <see cref="SerializationInfo"/> instance that defines the serialized data</param>
/// <param name="context">A <see cref="StreamingContext"/> instance that contains the serialized data</param>
[SecurityPermissionAttribute(SecurityAction.Demand,SerializationFormatter=true)]
public override void GetObjectData( SerializationInfo info, StreamingContext context )
{
base.GetObjectData( info, context );
info.AddValue( "schema2", schema2 );
}
#endregion
}
}