Understanding Python arrays-CodePudding

I am new to python & understanding the coding. I tried two sets of code, but for the below second line, I couldn't execute. can you plz explain why?

distance = np.array([0.723,1.0,1.524,5.203])
distance = [0.723,1.0,1.524,5.203]

flux = 1370 / (distance**2)

When I execute the second part (Line2) instead of first-line I get an error, Plz help me to understand:

TypeError: unsupported operand type(s) for ** or pow(): 'list' and 'int'

CodePudding user response：

If you work in form of list you have to iterate via for or while loop

One way is:-

distance = [0.723,1.0,1.524,5.203]
for i in distance:
    flux = 1370 / (i**2)
    print(flux)

Output:-

2620.8609049813576
1370.0
589.8622908356928
50.607270624669916

CodePudding user response：

You have iterate through distance

distance = [0.723,1.0,1.524,5.203]
new_distance = []
for d in distance:
    new_distance = 1370 / (d**2)
print(new_distance)

CodePudding user response：

You're getting the error because the second instantiated variable distance distance = [0.723,1.0,1.524,5.203] is a python list which doesn't support the power operator **.

So, you should just stick to numpy array.

distance = np.array([0.723,1.0,1.524,5.203])
flux = 1370 / (distance**2)

Which gives result array([2620.86090498, 1370., 589.86229084, 50.60727062])

You can get python list result if you want with:

>>> flux.tolist()
[2620.8609049813576, 1370.0, 589.8622908356928, 50.607270624669916]