Problem creating an array whose values are floats

I am new to MATLAB and I am trying to write a program which inputs an image and applies a filter based on the RGB values in each pixel. I am trying to linearize the RGB values so

   RedRatio = RedValue/(RedValue + GreenValue + BlueValue)
   GreenRatio = GreenValue/(RedValue + GreenValue + BlueValue)
   BlueRatio = BlueValue/(RedValue + GreenValue + BlueValue)

Where RedValue, GreenValue, and BlueValue are all uint8.

The problem I am having is RedRatio, GreenRatio, and BlueRatio are all returning either a 0 or a 1, where the values should be a decimal between 0 and 1.

Can someone help me get these ratios to return a decimal value?

Thanks,

-Tyler

Answer 1

[Geoff Hayes]

Tyler - try casting your numbers to floats before doing the division. For example,

 RedRatio = cast(RedValue,'double') / ...
      cast(RedValue + GreenValue + BlueValue, 'double');

Alternatively, you could try

RedRatio = double(RedValue) / ...
    double(RedValue + GreenValue + BlueValue);