How to create if dynamically in php

I want to create an if statement dynamically in PHP, but I don't know how to do this. For example, I am creating an Excel with different heights, widths and prices.

If my valueWidth < width the price is equal to the width price above.

If my width = 2050 and height = 2560, the prices is 621$.

The width, height and prices is entered dynamically and can be different from 3 numbers. Width, height and prices is Array.

width = [2000,3025,4036]
height = [2214,2411,2608]
class_1 = [245,272,302]
class_2 = [537,584,621]
class_3 = [755,799,836]
class_X = [...]

Can you help me find how to do the conditions effectively, please ?