Matlab – How to set the color scale in contourf function in MATLAB with arbitrary maximum and minimum values

colorscontourfillMATLABscaling

A simple question.
Is there anyway to tell the Matlab function "contourf", to scale the colors with my given values (and not the dataset's values) ?
I know that you can call the function simply by

contourf(x,y,Data, v)

and setting the range in the v vector, but my problem is that Matlab automatically checks whether or not the specified values in the v vector does actually exist in the Data? If they don't exist, then it automatically rescales the color range back to the maximum and minimum available in the dataset.

For instance, if

Data =[0 1 2; 3 4 5; 6 7 8]; 
v=-10:1:10;

then when I call

contourf(x,y,Data,v)

the colormap shown scales itself with

v=[0:8];

The reason I am asking for this is that I would like to several contour plots for various datasets, but I need to always have the same colorcode associated with the maximum/minimums that might not be necessarily in the current data array passed to the contourf function.

I hope I was clear enough.

Best Answer

Have a look at the caxis command. I haven't tested it with contourf, but I think this is what you're after.

Use it like so:

caxis([ cmin cmax ])

where cmin and cmax are the minimum and maximum colors given as indices into the current color map. From help caxis:

CAXIS is a function that sets the axes properties CLim and CLimMode.

meaning you can also tinker with these axes settings manually (i.e., set(gca, 'clim', [...]))

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Matlab – How to draw different surfaces with the same color scale in MATLAB

You should use the caxis function. For example, if one surface has a height from 0 to 5 and the other has a height from 0 to 10, doing the following for both plots:

caxis([0 10]);

will force them both to use the same color scale as the plot that covers the larger range. You can also call caxis with an axes handle as the first argument:

caxis(hAxes, [0 10]);  % Sets the color scaling for hAxes

If not specified, caxis adjusts the color scaling of the axes that is current.

Android – How to set the text color of TextView in code

You should use:

holder.text.setTextColor(Color.RED);

You can use various functions from the Color class to get the same effect of course.

Color.parseColor (Manual) (like LEX uses)

text.setTextColor(Color.parseColor("#FFFFFF"));

Color.rgb and Color.argb (Manual rgb) (Manual argb) (like Ganapathy uses)

holder.text.setTextColor(Color.rgb(200,0,0));
holder.text.setTextColor(Color.argb(0,200,0,0));

And of course, if you want to define your color in an XML file, you can do this:
```
<color name="errorColor">#f00</color>
```
because the getColor() function is deprecated¹, you need to use it like so:
```
ContextCompat.getColor(context, R.color.your_color);
```
You can also insert plain HEX, like so:
```
myTextView.setTextColor(0xAARRGGBB);
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Where you have an alpha-channel first, then the color value.

Check out the complete manual of course, public class Color extends Object.

¹This code used to be in here as well:

textView.setTextColor(getResources().getColor(R.color.errorColor));

This method is now deprecated in Android M. You can however use it from the contextCompat in the support library, as the example now shows.

Best Answer

Related Solutions

Matlab – How to draw different surfaces with the same color scale in MATLAB

Android – How to set the text color of TextView in code

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