Choosing randomly all the elements in the the list just once
- by Dalek
How is it possible to randomly choose a number from a list with n elements, n time without picking the same element of the list twice. I wrote a code to choose the sequence number of the elements in the list but it is slow:
>>>redshift=np.array([0.92,0.17,0.51,1.33,....,0.41,0.82])
>>>redshift.shape
(1225,)
exclude=[]
k=0
ng=1225
while (k < ng):
flag1=0
sq=random.randint(0, ng)
while (flag1<1):
if sq in exclude:
flag1=1
sq=random.randint(0, ng)
else:
print sq
exclude.append(sq)
flag1=0
z=redshift[sq]
k+=1
It doesn't choose all the sequence number of elements in the list.
