RAL color card and PANTONE color card corresponding number

RAL and PANTONE are two different brands, different brands of color research system is not the same, the naming method is not the same, so it is not a one-to-one correspondence, and then most of the price of the RAL color card is cheaper than the PANTONE color card, if it can be a one-to-one correspondence, then the PANTONE color card there is no need to exist. General can only find similar colors, one-to-one correspondence can not be found.