# Out of Bounds Colors in Color Bars

QUESTION: I would like to be able to show out-of-bounds or out-of-range colors on my color bar. Is it possible to do this with cgColorbar?

ANSWER: Yes, it is possible with the new OOB_Low and OOB_High keywords introduced on 11 December 2011. These keywords can be set to a particular color by specifying a color name (as understood by cgColor), a byte or short integer index into the current color table, or by specifying a three-element array representing a color triple. For example, these are all valid ways to specify the color yellow for the OOB_Low color.

```   OOB_Low='yellow'
OOB_Low = [255, 255, 0]

TVLCT, 255, 255, 0, 200
OOB_Low = 200B
```

The OOB_Low and OOB_High colors can be set independently of one another, so you can have no out-of-range colors, just the low, or just the high, or both, as you wish.

```    cgDisplay, XSize=500, YSize=300
cgColorbar, NColors=100, Position=[0.1, 0.8, 0.9, 0.85]
cgColorbar, NColors=100, Position=[0.1, 0.6, 0.9, 0.65], OOB_Low='rose'
cgColorbar, NColors=100, Position=[0.1, 0.4, 0.9, 0.45], OOB_High='dodger blue'
cgColorbar, NColors=100, Position=[0.1, 0.2, 0.9, 0.25], OOB_Low='rose', OOB_High='dodger blue'
```

You see the results in the figure below.

 Out of range colors can be used independently of each other.

You may find that you also have to control the size of the triangles that are using to draw the out-of-range colors. For example, consider this simple multiplot.

```    !P.Multi = [0,2,1]
!Y.OMargin = [1,5]
cgDisplay, XSize=500, YSize=350
data1 = cgDemoData(2)
data2 = cgDemoData(3)
cgContour, data1, NLevels=8,/Fill, C_Colors=Indgen(8)+1
cgColorbar, NColors=7, Bottom=1, OOB_High=8B, \$
OOB_Low='white', /Discrete, /Fit
cgContour, data2, NLevels=8, /Fill, C_Colors=Indgen(8)+1
cgColorbar, NColors=7, Bottom=1, OOB_High=8B, \$
OOB_Low='white', /Discrete, /Fit
!P.OMargin = [0,0]
!P.Multi=0
```

You see the results in the figure below.

 The out-of-range triangles are too large in this multiplot.

The out-of-range triangles are too large. You can reduce their size by using the OOB_Factor keyword. Here is a figure using the same code, but with the OOB_Factor=0.5 keyword added to the cgColorbar commands.

 The triangles are reduced in size by using the OOB_Factor keyword.