file io - Python program won't write full result to text -

in program, have loop calculates value of v, , prints text file:

def graph(): in range(0, len(t)-1):      stinum = np.floor(i / 3000)     stimt = 3000 + 3000 * (stinum - 1)      f[i] = v[i] * (1 - (((v[i]) ** 2) / 3))     v[i + 1] = 1 / c * (gna * f[i] - gk * u[i]) * del_t + v[i]      if(i == stimt):         v[i + 1] = v[i + 1] + v_stim      u[i + 1] = (v[i] + beta - gamma * u[i]) * del_t + u[i]  open("gna09.txt", "w") text_file:     text_file.write("v = {0}".format(v)) 

the problem text file looks this:

v = [[-1.1       ]  [-0.170828  ]  [-0.12414879]  ...,   [-1.13002606]  [-1.13002779]  [-1.13002954]] 

it's not printing out full results, realize lot, they're important , need them. there way can work? i'm newbie @ this, i'm not sure how go this. thank you.