How to use "nan"

I want to get rid of the color by using "nan" ,marked on the map.

The code is as follows.

[John D'Errico]

What does getting rid of a color mean here? Are you asking to replace those pixels with new ones that are blue, and look smoothly like the rest of the turbulent region in that area? Or do you just want to have a white area in that region, so essentially nothing plotted?

[gyeonggeun kim]

I want to change the pixels to blue and make them look as smooth as any other turbulent region in the area.

Answer 1

[Veronica Taurino]

Maybe this can help:

quiver plot - need help to remove NaN - MATLAB Answers - MATLAB Central (mathworks.com)

[gyeonggeun kim]

Thanks~

Answer 2

[KSSV]

LEt's say you want to change the values beyond a given value val (a number) into NaN. Use:

u(u>val) = NaN ; 

isnan is afunction used to check whether a value is nan or not. You can check after replacing values with NaN using:

u(isnan(u))

[gyeonggeun kim]

Thanks but it doesn't working.....

[KSSV]

Why do you think it is not working? Show us your code, attach your data.

[gyeonggeun kim]

u(u>=1) = NaN;

u(isnan(u))

I don't want white , I hope the yellow part doesn't show up.

[Veronica Taurino]

So you don't want BOTH white and yellow?

What do you want instead of white? Your request is not clear...

[gyeonggeun kim]

I'm sorry... um...

I don't want to be expressed under Japan!!

So I wish the Korean Strait would stand out better.

[Veronica Taurino]

...this is just worse than before ahah now I just get those blue shapes are Japan and Korea. But I don't get how this is answering to my previous question... I'm sorry

[gyeonggeun kim]

Thank you for trying to answer.

[KSSV]

If you replace values with NaN obviously it will show up as NaN. Instead of NaN replace it with a value.

[gyeonggeun kim]

u(u>nan) = 0 ;

like this?

[KSSV]

u(u>val) = 0 ;    % any number else from 0 also can be taken 

[gyeonggeun kim]

I will try it!! thank you