Michael Thomas Flanagan's Java Scientific Library

ErrorProp Class:     Error Propagation

      

Last update: 19 January 2005
This class defines an object consisting of a variable and its associated error (double variables named value and sd) and includes the methods for propagating the error in standard arithmetic operations for both correlated and uncorrelated errors. The error should be the standard deviation, or an estimate of the standard deviation, of the variable.



See ComplexErrorProp for error propagation in complex arithmetic.

import directive: import flanagan.analysis.ErrorProp; Related classes

SUMMARY OF CONSTRUCTORS AND METHODS
Constructors public ErrorProp()
  
public ErrorProp(double value, double sd)
  
public ErrorProp(double value)
  
Set Values public void setValue(double value)
  
public void setError(double sd)
  
public void reset(double value, double sd)
  
Get Values public double getValue()
  
public double getError()
  
public int hashCode()
  
Truncate mantissae to n places public ErrorProp truncate(int n) public static ErrorProp truncate(ErrorProp x, int n)
Print public void print(String message)
  
public void print()
  
public void println(String message)
  
public void println()
  
Conversions public String toString()
 public static String toString(ErrorProp aa)
public int hashCode()
  
Addition public ErrorProp plus(ErrorProp a) public static ErrorProp plus(ErrorProp a, ErrorProp b)
public ErrorProp plus(ErrorProp a, double corrCoeff) public static ErrorProp plus(ErrorProp a, ErrorProp b, double corrCoeff)
public ErrorProp plus(double a) public static ErrorProp plus(double a, ErrorProp b)
  public static ErrorProp plus(double a, double b)  
public ErrorProp plusEquals(ErrorProp a)
  
public ErrorProp plusEquals(ErrorProp a, double corrCoeff)
  
public ErrorProp plusEquals(double a)
  
Subtraction public ErrorProp minus(ErrorProp a) public static ErrorProp minus(ErrorProp a, ErrorProp b)
public ErrorProp minus(ErrorProp a, double corrCoeff) public static ErrorProp minus(ErrorProp a, ErrorProp b, double corrCoeff)
public ErrorProp minus(double a) public static ErrorProp minus(double a, ErrorProp b)
  public static ErrorProp minus(double a, double b)  
public ErrorProp minusEquals(ErrorProp a)
  
public ErrorProp minusEquals(ErrorProp a, double corrCoeff)
  
public ErrorProp minusEquals(double a)
  
Multiplication public ErrorProp times(ErrorProp a)
 public static ErrorProp times(ErrorProp a, ErrorProp b)
public ErrorProp times(ErrorProp a, double corrCoeff) public static ErrorProp times(ErrorProp a, ErrorProp b, double corrCoeff)
public ErrorProp times(double a)
 public static ErrorProp times(double a, ErrorProp b)
  public static ErrorProp times(double a, double b)
public ErrorProp timesEquals(ErrorProp a)
  
public ErrorProp timesEquals(ErrorProp a, double corrCoeff)  
public ErrorProp timesEquals(double a)
  
Division public ErrorProp over(ErrorProp a) public static ErrorProp over(ErrorProp a, ErrorProp b)
public ErrorProp over(ErrorProp a, double corrCoeff) public static ErrorProp over(ErrorProp a, ErrorProp b, double corrCoeff)
public ErrorProp over(double a)  
  public static ErrorProp over(double a, ErrorProp a)
  public static ErrorProp over(double a, double b)
public ErrorProp overEquals(ErrorProp a)  
public ErrorProp overEquals(ErrorProp a, double corrCoeff)  
public ErrorProp overEquals(double a)  
Reciprocal public ErrorProp inverse()
 public static ErrorProp inverse(ErrorProp a)
Exponential   public static ErrorProp exp(ErrorProp aa)
Logarithm   public static ErrorProp log(ErrorProp aa)
  public static ErrorProp log10(ErrorProp aa)
Root   public static ErrorProp sqrt(ErrorProp aa )
  public static ErrorProp nthRoot(ErrorProp aa, int n )
Power public ErrorProp square() public static ErrorProp square(ErrorProp aa)
  public static ErrorProp pow(ErrorProp a, ErrorProp b)
  public static ErrorProp pow(ErrorProp a, ErrorProp b, double corrCoeff)
  public static ErrorProp pow(ErrorProp a, double b)
  public static ErrorProp pow(ErrorProp a, int b)
  public static ErrorProp pow(double a, ErrorProp b)
  public static ErrorProp pow(int a, ErrorProp b)
Trigonometric
Functions 		  public static ErrorProp sin(ErrorProp aa )
  public static ErrorProp asin(ErrorProp aa )
  public static ErrorProp cos(ErrorProp aa )
  public static ErrorProp acos(ErrorProp aa )
  public static ErrorProp tan(ErrorProp aa )
  public static ErrorProp atan(ErrorProp aa )
  public static ErrorProp atan2(ErrorProp aa, ErrorProp bb)
  public static ErrorProp atan2(ErrorProp aa, ErrorProp bb, double corrCoeff)
  public static ErrorProp sinh(ErrorProp aa )
  public static ErrorProp asinh(ErrorProp aa )
  public static ErrorProp cosh(ErrorProp aa )
  public static ErrorProp acosh(ErrorProp aa )
  public static ErrorProp tanh(ErrorProp aa )
  public static ErrorProp atanh(ErrorProp aa )
Hypotenuse   public static double hypot(ErrorProp a, ErrorProp b)
  public static double hypot(ErrorProp aa, ErrorProp bb, double corrCoeff)
Arrays   public static ErrorProp[] oneDarray(int n)
  public static ErrorProp[] oneDarray(int n, double a, double b)
  public static ErrorProp[] oneDarray(int n, ErrorProp xx)
  public static ErrorProp[][] twoDarray(int n, int m)
  public static ErrorProp[][] twoDarray(int n, int m, double a, double b)
  public static ErrorProp[][] twoDarray(int n, int m, ErrorProp xx)
Deep Copy public ErrorProp copy()
 public static ErrorProp copy(ErrorProp a)
public Object clone()
  
  public static ErrorProp[] copy(ErrorProp[] a)
  public static ErrorProp[][] copy(ErrorProp[][] a)
Some Useful
Numbers 		  public static ErrorProp zero()
  public static ErrorProp plusOne()
  public static ErrorProp minusOne()


CONSTRUCTORS

public ErrorProp()
Usage:                      ErrorProp aa = new ErrorProp();
This creates a new instance of ErrorProp(), aa, and initialises both the value (value) and the error (sd) to zero

public ErrorProp(double value, double sd)
Usage:                      ErrorProp aa = new ErrorProp(x, y);
This creates a new instance of ErrorProp(), aa, and initialises the value (value) to x and the error (sd) to y

public ErrorProp(double value)
Usage:                      ErrorProp aa = new ErrorProp(x);
This creates a new instance of ErrorProp(), aa, and initialises the value part (value) to x and the error (sd) to zero


METHODS

SET VALUES
public void setValue(double value)
Usage:                      aa.setValue(x);
Sets the value of the existing ErrorProp aa to x

public void setError(double sd)
Usage:                      aa.setError(x);
Sets the error (sd) of the existing ErrorProp aa to x

public void reset(double value, double sd)
Usage:                      aa.reset(x, y);
Sets the value of the existing ErrorProp aa to x and the error (sd) to y


GET VALUES
public double getValue()
Usage:                      x = aa.getValue();
The value of the ErrorProp number represented by aa is returned to x.

public double getError()
Usage:                      x = aa.getError();
The sd (error) of the ErrorProp number represented by aa is returned to x.

Return a hash code for the ErrorProp number
public int hashCode()
Usage:                      hc = aa.hashCode();
The hashcode for aa is returned to hc.
Overrides java.lang.Object.hashCode()


Write an ErrorProp Instance

Write an ErrorProp Instance to Screen public void print(String message)
public void print()
Example of Usage:                     aa.print("The value of the ErrorProp number aa is");
Writes to the screen, e.g. the workstation terminal window, the MSDOS window, the message followed by the value of the ErrorProp number (in aa in the above example) in the form: value, error = sd.
Usage:                     aa.print();
Writes to the screen, e.g. the workstation terminal window, the MSDOS window, the value of a ErrorProp number (in aa in the above example) in the form: value, error = sd.

public void println(String message)
public void println()
Example of Usage:                     aa.println("The value of the ErrorProp number aa is");
Writes to the screen, e.g. the workstation terminal window, the MSDOS window, the message followed by the value of the ErrorProp number (in aa in the above example) in the form: value, error = sd followed by a line return.
Usage:                     aa.println();
Writes to the screen, e.g. the workstation terminal window, the MSDOS window, the value of a ErrorProp number (in aa in the above example) in the form: value, error = sd followed by a line return.

Convert an ErrorProp Instance to a String
public String toString()
public static String toString(ErrorProp a)
Usage:                      ss = aa.toString();
Usage:                      ss = ErrorProp.toString(aa);
Converts the ErrorProp number in aa to a string (referenced by ss in the above example) of the form: value, error = sd.
This method overides java.lang.String.toString(). Consequently you may add an ErrorProp number to the string in the standard output methods, e.g. System.out.print(), System.out.println(), g.drawString, and it will automatically be converted to the value, error = sd format on output.


TRUNCATE MANTISSAE TO N PLACES
Instance method
public ErrorProp truncate(int n)
Usage:                      xt=x.truncate(n);
Returns the value of x with the mantissae of both the value and error parts rounded to n decimal places, If the argument indicating the number of places before truncation, i.e. n in the above example, is any negative integer, the variable to be truncated, i.e. x in the above example, is returned without truncation. This method can be useful in outputting data.

Static method
public static ErrorProp truncate(ErrorProp x, int n)
Usage:                      xt = ErrorProp.truncate(x, n);
Returns the value of x with the mantissae of both the real and imaginary parts rounded to n decimal places. If the argument indicating the number of places before truncation, i.e. n in the above example, is any negative integer, the variable to be truncated, i.e. x in the above example, is returned without truncation. This method can be useful in outputting data.


ADDITION
Instance methods - Uncorrelated errors
public ErrorProp plus(ErrorProp a)
public ErrorProp plus(double a)
Usage:                      z = x.plus(y);
Performs the operation z = x + y and propagates the addition error, where z and x are ErrorProp and y may be either ErrorProp or double (i.e. value)

Instance methods - Correlated errors
public ErrorProp plus(ErrorProp a, double corrcoeff)
Usage:                      z = x.plus(y, rho);
Performs the operation z = x + y and propagates the addtion error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Static methods - Uncorrelated errors
public static ErrorProp plus(ErrorProp a, ErrorProp b)
public static ErrorProp plus(double a, ErrorProp b)
public static ErrorProp plus(double a, double b)
Usage:                      z = ErrorProp.plus(x, y);
Performs the operation z = x + y and propagates the addtion error, where z is ErrorProp and x and y may be both ErrorProp, double and ErrorProp respectively or both double

Static methods - Correlated errors
public static ErrorProp plus(ErrorProp a, ErrorProp b, double corrcoeff)
Usage:                      z = ErrorProp.plus(x, y, rho);
Performs the operation z = x + y and propagates the addtion error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Equivalence of the += operator - Uncorrelated errors
public void plusEquals(ErrorProp a )
public void plusEquals(double a )
Usage:                      x.plusEquals(y);
Performs the operation x = x + y and propagates the addition error, where x is ErrorProp and y may be either ErrorProp or double (i.e. value)

Equivalence of the += operator - Correlated errors
public void plusEquals(ErrorProp a, double corrCoeff)
Usage:                      x.plusEquals(y, rho);
Performs the operation x = x + y and propagates the addition error with a correlation coefficient, rho, where x and y are ErrorProp.


SUBTRACTION
Instance methods - Uncorrelated errors
public ErrorProp minus(ErrorProp a)
public ErrorProp minus(double a)
Usage:                      z = x. minus(y);
Performs the operation z = x - y and propagates the subtraction error, where z and x are ErrorProp and y may be either ErrorProp or double (i.e. value)

Instance methods - Correlated errors
public ErrorProp minus(ErrorProp a, double corrcoeff)
Usage:                      z = x.minus(y, rho);
Performs the operation z = x - y and propagates the subtraction error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Static methods - Uncorrelated errors
public static ErrorProp minus(ErrorProp a, ErrorProp b)
public static ErrorProp minus(double a, ErrorProp b)
public static ErrorProp minus(double a, double b)
Usage:                      z = ErrorProp. minus(x, y);
Performs the operation z = x - y and propagates the subtraction error, where z is ErrorProp and x and y may be both ErrorProp, double and ErrorProp respectively or both double.

Static methods - Correlated errors
public static ErrorProp minus(ErrorProp a, ErrorProp b, double corrcoeff)
Usage:                      z = ErrorProp. minus(x, y, rho);
Performs the operation z = x - y and propagates the subtraction error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Equivalence of the -= operator - Uncorrelated errors
public void minusEquals(ErrorProp a )
public void minusEquals(double a )
Usage:                      x. minusEquals(y);
Performs the operation x = x - y and propagates the subtraction error, where x is ErrorProp and y may be either ErrorProp or double (i.e. value)

Equivalence of the -= operator - Correlated errors
public void minusEquals(ErrorProp a, double corrCoeff)
Usage:                      x. minusEquals(y, rho);
Performs the operation x = x - y and propagates the subtraction error with a correlation coefficient, rho, where x and y are ErrorProp.


MULTIPLICATION
Instance methods - Uncorrelated errors
public ErrorProp times(ErrorProp a)
public ErrorProp times(double a)
Usage:                      z = x.times(y);
Performs the operation z = x*y and propagates the multiplication error, where x and z are ErrorProp and y may be either ErrorProp or double.

Instance methods - Correlated errors
public ErrorProp times(ErrorProp a, double corrCoeff)
Usage:                      z = x.times(y, rho);
Performs the operation z = x*y and propagates the multiplication error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Static methods - Uncorrelated errors
public static ErrorProp times(ErrorProp a, ErrorProp b)
public static ErrorProp times(double a, ErrorProp b)
public static ErrorProp times(double a, double b)
Usage:                      z = ErrorProp.times(x, y);
Performs the operation z = x*y and propagates the multiplication error, where z is always ErrorProp but x and y may be both ErrorProp, double and ErrorProp respectively or both double.

Static methods - Correlated errors
public static ErrorProp times(ErrorProp a, ErrorProp b, double corrCoeff)
Usage:                      z = ErrorProp.times(x, y, rho);
Performs the operation z = x*y and propagates the multiplication error with a correlation coefficient, rho , where x, y and z are ErrorProp.

Equivalence of the *= operator - Uncorrelated errors
public void timesEquals(ErrorProp a )
public void timesEquals(double a )
Usage:                      x.timesEquals(y);
Performs the operation x = x*y and propagates the multiplication error, where x is ErrorProp and y may be either ErrorProp or double.

Equivalence of the *= operator - Correlated errors
public void timesEquals(ErrorProp a, double corrCoeff)
Usage:                      x.timesEquals(y, rho);
Performs the operation x = x*y and propagates the multiplication error with a correlation coefficient, rho, where x and y are ErrorProp.


DIVISION
Instance methods - Uncorrelated errors
public ErrorProp over(ErrorProp a)
public ErrorProp over(double a)
Usage:                      z = x.over(y);
Performs the operation z = x/y and propagates the division error, where z and x are ErrorProp and y may be either ErrorProp or double (i.e. value)

Instance methods - Correlated errors
public ErrorProp over(ErrorProp a, double corrCoeff)
Usage:                      z = x.over(y, rho);
Performs the operation z = x/y and propagates the division error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Static methods - Uncorrelated errors
public static ErrorProp over(ErrorProp a, ErrorProp b)
public static ErrorProp over(double a, ErrorProp b)
public static ErrorProp over(double a, double b)
Usage:                      z = ErrorProp.over(x, y);
Performs the operation z = x/y and propagates the division error, where z is ErrorProp and x and y may both ErrorProp, ErrorProp and double respectively or both double.

Static methods - Correlated errors
public static ErrorProp over(ErrorProp a, ErrorProp b, double corrCoeff)
Usage:                      z = ErrorProp.over(x, y, rho);
Performs the operation z = x/y and propagates the division error with a correlation coefficient, rho, where x, y and z are ErrorProp.

Equivalence of the /= operator - Uncorrelated errors
public void overEquals(ErrorProp a )
public void overEquals(double a )
Usage:                      x.overEquals(y);
Performs the operation x = x/y and propagates the division error, where x is ErrorProp and y may be either ErrorProp or double (i.e. value)

Equivalence of the /= operator - Correlated errors
public void overEquals(ErrorProp a, double corrCoeff)
Usage:                      x.overEquals(y, rho);
Performs the operation x = x/y and propagates the division error with a correlation coefficient, rho, where x and y are ErrorProp.


RECIPROCAL
Invert a ErrorProp number
public ErrorProp inverse()
public static ErrorProp inverse(ErrorProp a)
Usage:                      x = y.inverse();
Usage:                      x = ErrorProp.inverse(y);
Performs the operation x = 1.0/y and propagates the error.


EXPONENTIALS
Returns the exponential of a ErrorProp number and propagates the error.
public static ErrorProp exp(ErrorProp aa)
Usage:                      x = ErrorProp.exp(y);
where x and y are ErrorProp.


LOGARITHMS
Returns the natural log of an ErrorProp number and propagates the error.
public static ErrorProp log(ErrorProp aa )
Usage:                      x = ErrorProp.log(y);

Returns the log to base 10 of an ErrorProp number and propagates the error.
public static ErrorProp log(ErrorProp aa)
Usage:                      x = ErrorProp.log10(y);


ROOTS
Returns of the square root of a ErrorProp number and propagates the error.
public static ErrorProp sqrt(ErrorProp aa )
Usage:                      x = ErrorProp.sqrt(y);

Returns the nth root of a ErrorProp number and propagates the error.
public static ErrorProp nthRoot(ErrorProp aa, int n )
Usage:                      x = ErrorProp.nthRoot(y, n);
Performs the operation x = the nth root of y where y is ErrorProp and n is an integer (type int) greater than zero.


POWERS
public ErrorProp square()
public static ErrorProp square(ErrorProp aa)
Usage:                      x = y.square();
Usage:                      x = ErrorProp.square(y);
Returns the square of a ErrorProp number and propagates the error.

public static ErrorProp pow(ErrorProp a, ErrorProp b)
public static ErrorProp pow(ErrorProp a, int b)
public static ErrorProp pow(ErrorProp a, double b)
public static ErrorProp pow(int a, ErrorProp b)
public static ErrorProp pow(double a, ErrorProp b)
Usage:                      z = ErrorProp.pow(x, y);
Returns x raised to the power y as z and propagates the error, where z is ErrorProp and x and y may be int, double or ErrorProp.

public static ErrorProp pow(ErrorProp a, ErrorProp b, double corrCoeff)
Usage:                      z = ErrorProp.pow(x, y, rho);
Returns x raised to the power y as z and propagates the error with a correlation coefficient, rho, where x, y and z are ErrorProp and x.


TRIGONOMETRIC FUNCTIONS
General Usage:                     x = ErrorProp.funct(y);
where funct is the trigonometric function, e.g. sin. Returns the value of the trigonometric function and the propagated error.

Sine of an ErrorProp number
public static ErrorProp sin(ErrorProp a)
Cosine of an ErrorProp number
public static ErrorProp cos(ErrorProp a)
Tangent of an ErrorProp number
public static ErrorProp tan(ErrorProp a)
Hyperbolic sine of a ErrorProp number
public static ErrorProp sinh(ErrorProp a)
Hyperbolic cosine of a ErrorProp number
public static ErrorProp cosh(ErrorProp a)
Hyperbolic tangent of a ErrorProp number
public static ErrorProp tanh(ErrorProp a)

Inverse sine of a ErrorProp number
public static ErrorProp asin(ErrorProp a)
Inverse cosine of a ErrorProp number
public static ErrorProp acos(ErrorProp a)
Inverse tangent of a ErrorProp number
public static ErrorProp atan(ErrorProp a)
public static ErrorProp atan2(ErrorProp aa, ErrorProp bb)
public static ErrorProp atan2(ErrorProp aa, ErrorProp bb, double corrCoeff)
Inverse hyperbolic sine of a ErrorProp number
public static ErrorProp asinh(ErrorProp a)
Inverse hyperbolic cosine of a ErrorProp number
public static ErrorProp acosh(ErrorProp a)
Inverse hyperbolic tangent of a ErrorProp number
public static ErrorProp atanh(ErrorProp a)


HYPOTENUSE
public static double hypot(ErrorProp a, ErrorProp b)
Usage:                      d = ErrorProp.hypot(a, b);
Returns the length of the hypotenuse of a and b, i.e. sqrt(a*a + b*b) where a and b are ErrorProp and propagates the error. This method avoids unecessary overflow or underflow.

public static double hypot(ErrorProp a, ErrorProp b, double corrCoeff)
Usage:                      d = ErrorProp.hypot(a, b, rho);
Returns the length of the hypotenuse of a and b, i.e. sqrt(a*a + b*b) where a and b are ErrorProp and propagates the error with a correlation coefficient, rho. This method avoids unecessary overflow or underflow.


TYPE CONVERSIONS
ErrorProp to String
public String toString()
public static String toString(ErrorProp a)
Usage:                      ss = aa.toString();
Usage:                      ss = ErrorProp.toString(aa);
Converts the ErrorProp number in aa to a string (referenced by ss in the above example) of the form: value, error = sd.
This method overides java.lang.String.toString(). Consequently you may add an ErrorProp number to the string in the standard output methods, e.g. System.out.print(), System.out.println(), g.drawString, and it will automatically be converted to the value, error = sd format on output.

ErrorProp to hashcode
public int hashCode()
Usage:                      hc = aa.hashCode();
The hashcode for aa is returned to hc.
Overides java.lang.Object.hashCode()


ARRAYS
Vectors
public static ErrorProp[] oneDarray(int n)
public static ErrorProp[] oneDarray(int n, double a, double b)
public static ErrorProp[] oneDarray(int n, ErrorProp xx)

Create a one dimensional array of ErrorProp objects of length n with all value = zero and all sd = zero
Usage:                      ErrorProp[] aa = ErrorProp.oneDarray(n);

Create a one dimensional array of ErrorProp objects of length n with all value = x and all sd = y
Usage:                      ErrorProp[] aa = ErrorProp.oneDarray(n, x, y);

Create a one dimensional array of ErrorProp objects of length n with all array objects = the ErrorProp zz
Usage:                      ErrorProp[] aa = ErrorProp.oneDarray(n, zz);

Matrices
public static ErrorProp[][] twoDarray(int n, int m)
public static ErrorProp[][] twoDarray(int n, int m, double a, double b)
public static ErrorProp[][] twoDarray(int n, int m, ErrorProp xx)

Create a two dimensional array (matrix) of ErrorProp objects of dimensions n and m with all value = zero and all sd = zero
Usage:                      ErrorProp[][] aa = ErrorProp.twoDarray(n, m);

Create a two dimensional array (matrix) of ErrorProp objects of dimensions n and m with all value = a and all sd = b
Usage:                      ErrorProp[][] aa = ErrorProp.twoDarray(n, m, x, y);

Create a two dimensional array (matrix) of ErrorProp objects of dimensions n and m with all ErrorProp objects in the matrix = the ErrorProp zz
Usage:                      ErrorProp[][] aa = ErrorProp.twoDarray(n, m, zz);


COPY
REMEMBER: aa = bb; does not copy bb into aa when aa and bb are objects, instead aa becomes a reference to bb.
public ErrorProp copy()
public Object clone()
public static ErrorProp copy(ErrorProp a)
public static ErrorProp[] copy(ErrorProp[] a)
public static ErrorProp[][] copy(ErrorProp[][] a)

Copy a single ErrorProp number
Usage:                      aa = bb.copy();
Usage:                      aa = ErrorProp.copy(bb);
The ErrorProp number, bb, is copied and returned to aa.

Clone a single ErrorProp number
Usage:                      aa = (ErrorProp) bb.clone();
The ErrorProp number, bb, is copied and returned to aa. This method overrides java.lang.Object.clone().

Copy a 1D array of ErrorProp numbers (deep copy)
Usage:                      aa = ErrorProp.copy(bb);
The ErrorProp 1D array, bb, is copied and returned to aa.

Copy a 2D array of ErrorProp numbers (deep copy)
Usage:                      aa = ErrorProp.copy(bb);
The ErrorProp 2D array, bb, is copied and returned to aa.


SOME USEFUL NUMBERS
Return the number zero (0) as a ErrorProp number with value = 0.0 and sd = 0.0.
public static ErrorProp zero()
Usage:                      x = ErrorProp.zero();


Return the number one (+1) as a ErrorProp number with value = 1.0 and sd = 0.0.
public static ErrorProp plusOne()
Usage:                      x = ErrorProp.plusOne();

 Return the number minus one (-1) as a ErrorProp number with value = -1.0 and sd = 0.0.
public static ErrorProp minusOne()
Usage:                      x = ErrorProp.minusOne();



OTHER CLASSES USED BY THIS CLASS

 This class uses the following classes in this library:

This page was prepared by Dr Michael Thomas Flanagan