Trying to store values and loop calculations from a function-CodePudding

The equation requires the previous output to calculate the next value. Vi = V(i-1) t((c*(V(i-1)^2)/m)-g). With V(0)=0 and all other values being defined I am not sure how to write a loop code that would store the previous value and then calculate the next iteration. I've tried a def approach but I could never figure out how to recall the previous calculation to use in the next step.

  Vi = Vo   Dt*((c*(Vo**2)/m)-g)
  return Vi

CodePudding user response：

Assuming t, c, m, and g are constants you can pass them to the recursive function:

def V(input, t, c, m, g) -> int:
    if input == 0: return 0
    return V(input - 1, t, c, m, g)   t( (c * (V(input - 1, t, c, m, g) ** 2) / m) -g)

CodePudding user response：

A recursive solution, where you define each value of v relative to the prior value, might look like this:

def calculate_v(i):
    if i == 0:
        return 0
    v = calculate_v(i - 1)
    return v   t * (c * v ** 2 / m - g)

whereas an iterative solution, where you just re-calculate v i times, would look like:

def calculate_v(i):
    v = 0
    for _ in range(i):
        v = v   t * (c * v ** 2 / m - g)
    return v