Python convert string into variable then use in function

Question

I've generated a variable names for pN from N=0 to n:

p0, p1, p2, p3, p4,....,pn

So far I got:

P = ['p0', 'p1', 'p2',..., 'pn']

What I want to do now is convert them into variable names to be called upon and used in a function. Convert 'p0' to p0, and so on for all of the values in

P = ['p0', 'p1', 'p2',..., 'pn']

So it becomes

P = [p0, p1, p2,..., pn]

Then generate functions using the variables:

Fi = P[i]/2

ie:

F0 = p0/2
F1 = p1/2
F2 = p2/2

Problem is I don't know how to convert 'pn' to pn properly, then generate functions based on pn. How do I do that? Or rather, what am I doing wrong?

Here's what I got:

# Define the constants
# ====================
k = 1
m = 1

# Generate the names
# ==================
n = 10 # Number of terms
P = [] # Array for momenta names
Q = [] # Array for positon names
for i in range (n): # Generate the names for
    p = "p"+str(i)  # momentum
    q = "q"+str(i)  # positon
    # Convert the names into variales
    exec("%s = %d" % p)
    exec("%s = %d" % q)
    # Put the names into the arrays
    P.append(p)
    Q.append(q)
# Print the names out for error checking
print(P)
print(Q)

# Generate the functions
# ======================
Q_dot = []

for i in range(n):
    def Q_dot(P[i]):
        q_dot = P[i] / m
        Q_dot.append(q_dot)
    i += 1

Note: I want to keep my variables as variables because I'm using the functions to solve a system of differential equations. My goal is to create a list of differential equations with the same format.

You should look into dictionaries. Not only is your current approach difficult to build and maintain but you do yourself no favours having all these variables floating around. — roganjosh, Mar 21 '18 at 19:57
Possible duplicate of [How do I create a variable number of variables?](https://stackoverflow.com/questions/1373164/how-do-i-create-a-variable-number-of-variables) — user3483203, Mar 21 '18 at 20:00
I did. The problem with that is that I have to assign a value to each of the variables, which I don't want to do because I'm using the variables to solve a differential equation. — Kevin, Mar 21 '18 at 20:00
Use a *container* like a list or a dict, don't use a bunch of variables with dynamic execution using `exec`. That's a really bad design — juanpa.arrivillaga, Mar 21 '18 at 20:00
I don't think the items I create in a list are variable, since the function I created don't recognize them as variables whet it is called upon. What should I do to have them be recognized as variables? — Kevin, Mar 21 '18 at 20:14

Python convert string into variable then use in function

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