tensorflow can not find GPU

Question

I installed TensorFlow-GPU 2.1.0 but when asked the version the answer is 1.13.1

import tensorflow as tf
print(tf.__version__)

the big problem is when I run the GPU test the answer is False

tf.test.is_gpu_available()

I tried this

print("Num GPUs Available:",len(tf.config.experimental.list_physical_devices('GPU')))

the answer is AttributeError: module 'tensorflow' has no attribute 'config' but he I run this script

from numba import vectorize, jit, cuda  
# to measure exec time 
from timeit import default_timer as timer 
# normal function to run on cpu 
def func(a):                                 
   for i in range(10000000): 
       a[i]+= 1    
# function optimized to run on gpu 
@vectorize(['float64(float64)'], target ="cuda")                         
def func2(x): 
    return x+1
# kernel to run on gpu
@cuda.jit
def func3(a, N):
    tid = cuda.grid(1)
    if tid < N:
        a[tid] += 1
if __name__=="__main__": 
    n = 10000000                            
    a = np.ones(n, dtype = np.float64) 
    for i in range(0,5):
         start = timer() 
         func(a) 
         print(i, " without GPU:", timer()-start)     
    for i in range(0,5):
         start = timer() 
         func2(a) 
         print(i, " with GPU ufunc:", timer()-start) 
    threadsperblock = 1024
    blockspergrid = (a.size + (threadsperblock - 1)) // threadsperblock
    for i in range(0,5):
         start = timer() 
         func3[blockspergrid, threadsperblock](a, n) 
         print(i, " with GPU kernel:", timer()-start) 

the answers are 0 without GPU: 5.481482100000051 1 without GPU: 5.6241342000000145 2 without GPU: 5.62558580000001 3 without GPU: 5.299320899999998 4 without GPU: 5.424306600000023 0 with GPU ufunc: 0.4764495000000011 1 with GPU ufunc: 0.118225099999961 2 with GPU ufunc: 0.12550920000001042 3 with GPU ufunc: 0.11633530000000292 4 with GPU ufunc: 0.11252430000001823 0 with GPU kernel: 0.20753619999999273 1 with GPU kernel: 0.08865670000000136 2 with GPU kernel: 0.08246159999998781 3 with Z52F9EC21735243AD9917 CDA3CA077D32Z kernel: 0.08481519999998 4 with GPU kernel: 0.08220890000001191 How can I make the GPU visible for TensorFlow?

Answer 1

The problem was due to the presence of two Cuda versions (10 and 11) on my device. I uninstalling the Cuda 10 and then the problem was solved