converting a decimal number into color code using Opencv [closed]

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I have an array of 3d points,for example: AR = {(1,0,0) , (0.3,0.4,-0.5) , .... } where the norm of each element is between 0 and 1

I want to draw an image using Opencv and to convert each element ( the norm that is between 0 annd 1) into a color in each pixel

 Vec3b color = image.at<cv::Vec3b>(cv::Point(x,y));
 color.val[0] = // what should I add here 
 color.val[1] = // what should I add here 
 color.val[2] =  // what should I add here