FreeHEP API
Version 3.2.1

## hep.aida Interface IHistogram2D

All Superinterfaces:
IBaseHistogram, IHistogram

public interface IHistogram2D
extends IHistogram

User level interface to 2D Histogram.

Author:
The AIDA team (http://aida.freehep.org/)

 Method Summary ` void` `add(IHistogram2D hist)`           Add to this IHistogram2D the contents of another IHistogram2D. ` int` ```binEntries(int indexX, int indexY)```           Number of entries in the corresponding bin (ie the number of times fill was called for this bin). ` int` `binEntriesX(int index)`           Sum of all the entries of the bins along a given x bin. ` int` `binEntriesY(int index)`           Sum of all the entries of the bins along a given y bin. ` double` ```binError(int indexX, int indexY)```           The error of a given bin. ` double` ```binHeight(int indexX, int indexY)```           Total height of a give bin (ie the sum of the weights in this bin). ` double` `binHeightX(int index)`           Sum of all the heights of the bins along a given x bin. ` double` `binHeightY(int index)`           Sum of all the heights of the bins along a given y bin. ` double` ```binMeanX(int indexX, int indexY)```           The weighted mean along the x axis of a given bin. ` double` ```binMeanY(int indexX, int indexY)```           The weighted mean along the y axis of a given bin. ` int` `coordToIndexX(double coord)`           Get the bin number corresponding to a given coordinate along the x axis. ` int` `coordToIndexY(double coord)`           Get the bin number corresponding to a given coordinate along the y axis. ` void` ```fill(double x, double y)```           Fill the IHistogram2D with a couple of values and the corresponding weight. ` void` ```fill(double x, double y, double weight)```           Fill the IHistogram2D with a couple of values and the corresponding weight. ` double` `meanX()`           The mean of the IHistogram2D along the x axis. ` double` `meanY()`           The mean of the IHistogram2D along the y axis. ` double` `rmsX()`           The RMS of the IHistogram2D along the x axis. ` double` `rmsY()`           The RMS of the IHistogram2D along the y axis. ` IAxis` `xAxis()`           Get the x axis of the IHistogram2D. ` IAxis` `yAxis()`           Get the y axis of the IHistogram2D.

 Methods inherited from interface hep.aida.IHistogram `allEntries, equivalentBinEntries, extraEntries, maxBinHeight, minBinHeight, scale, sumAllBinHeights, sumBinHeights, sumExtraBinHeights`

 Methods inherited from interface hep.aida.IBaseHistogram `annotation, dimension, entries, reset, setTitle, title`

 Method Detail

### fill

```public void fill(double x,
double y)
throws IllegalArgumentException```
Fill the IHistogram2D with a couple of values and the corresponding weight.

Parameters:
`x` - The x value to be filled in.
`y` - The y value to be filled in.
Throws:
`IllegalArgumentException` - If the weight is <0 or >1 (?).

### fill

```public void fill(double x,
double y,
double weight)
throws IllegalArgumentException```
Fill the IHistogram2D with a couple of values and the corresponding weight.

Parameters:
`x` - The x value to be filled in.
`y` - The y value to be filled in.
`weight` - The corresponding weight (by default 1).
Throws:
`IllegalArgumentException` - If the weight is <0 or >1 (?).

### binMeanX

```public double binMeanX(int indexX,
int indexY)
throws IllegalArgumentException```
The weighted mean along the x axis of a given bin.

Parameters:
`indexX` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
`indexY` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The mean of the corresponding bin along the x axis.
Throws:
`IllegalArgumentException` - If the indexes are not a valid bin number.

### binMeanY

```public double binMeanY(int indexX,
int indexY)
throws IllegalArgumentException```
The weighted mean along the y axis of a given bin.

Parameters:
`indexX` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
`indexY` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The mean of the corresponding bin along the y axis.
Throws:
`IllegalArgumentException` - If the indexes are not a valid bin number.

### binEntries

```public int binEntries(int indexX,
int indexY)
throws IllegalArgumentException```
Number of entries in the corresponding bin (ie the number of times fill was called for this bin).

Parameters:
`indexX` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
`indexY` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The number of entries in the corresponding bin.
Throws:
`IllegalArgumentException` - If the indexes are not a valid bin number.

### binEntriesX

```public int binEntriesX(int index)
throws IllegalArgumentException```
Sum of all the entries of the bins along a given x bin. This is equivalent to projectionX().binEntries(index).

Parameters:
`index` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The number of entries in the corresponding set of bins.
Throws:
`IllegalArgumentException` - If the index id not a valid bin number.

### binEntriesY

```public int binEntriesY(int index)
throws IllegalArgumentException```
Sum of all the entries of the bins along a given y bin. This is equivalent to projectionY().binEntries(index).

Parameters:
`index` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The number of entries in the corresponding set of bins.
Throws:
`IllegalArgumentException` - If the index id not a valid bin number.

### binHeight

```public double binHeight(int indexX,
int indexY)
throws IllegalArgumentException```
Total height of a give bin (ie the sum of the weights in this bin).

Parameters:
`indexX` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
`indexY` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The height of the corresponding bin.
Throws:
`IllegalArgumentException` - If the indexes are not a valid bin number.

### binHeightX

```public double binHeightX(int index)
throws IllegalArgumentException```
Sum of all the heights of the bins along a given x bin. This is equivalent to projectionX().binHeight(index).

Parameters:
`index` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The sum of the heights in the corresponding set of bins.
Throws:
`IllegalArgumentException` - If the index id not a valid bin number.

### binHeightY

```public double binHeightY(int index)
throws IllegalArgumentException```
Sum of all the heights of the bins along a given y bin. This is equivalent to projectionY().binHeight(index).

Parameters:
`index` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The sum of the heights in the corresponding set of bins.
Throws:
`IllegalArgumentException` - If the index id not a valid bin number.

### binError

```public double binError(int indexX,
int indexY)
throws IllegalArgumentException```
The error of a given bin.

Parameters:
`indexX` - The x bin number (0...N-1) or OVERFLOW or UNDERFLOW.
`indexY` - The y bin number (0...N-1) or OVERFLOW or UNDERFLOW.
Returns:
The error on the corresponding bin.
Throws:
`IllegalArgumentException` - If the indexes are not a valid bin number.

### meanX

`public double meanX()`
The mean of the IHistogram2D along the x axis.

Returns:
The mean of the IHistogram2D along the x axis.

### meanY

`public double meanY()`
The mean of the IHistogram2D along the y axis.

Returns:
The mean of the IHistogram2D along the y axis.

### rmsX

`public double rmsX()`
The RMS of the IHistogram2D along the x axis.

Returns:
The RMS if the IHistogram2D along the x axis.

### rmsY

`public double rmsY()`
The RMS of the IHistogram2D along the y axis.

Returns:
The RMS if the IHistogram2D along the y axis.

### xAxis

`public IAxis xAxis()`
Get the x axis of the IHistogram2D.

Returns:
The x coordinate IAxis.

### yAxis

`public IAxis yAxis()`
Get the y axis of the IHistogram2D.

Returns:
The y coordinate IAxis.

### coordToIndexX

`public int coordToIndexX(double coord)`
Get the bin number corresponding to a given coordinate along the x axis. This is a convenience method, equivalent to xAxis().coordToIndex(coord).

Parameters:
`coord` - The coordinalte along the x axis.
Returns:
The corresponding bin number.
`IAxis.coordToIndex(double)`

### coordToIndexY

`public int coordToIndexY(double coord)`
Get the bin number corresponding to a given coordinate along the y axis. This is a convenience method, equivalent to yAxis().coordToIndex(coord).

Parameters:
`coord` - The coordinalte along the y axis.
Returns:
The corresponding bin number.
`IAxis.coordToIndex(double)`

```public void add(IHistogram2D hist)
throws IllegalArgumentException```
Add to this IHistogram2D the contents of another IHistogram2D.

Parameters:
`hist` - The IHistogram2D to be added to this IHistogram2D.
Throws:
`IllegalArgumentException` - If the IHistogram2Ds binnings are incompatible.

FreeHEP API
Version 3.2.1