beginner : unexpected EOF errors

[upasana]

Hi..
I am new to python programming. I am trying to generate a raster plot here.

my code:

from brian2 import *
import matplotlib


start_scope()
cnt=1
ct=0
f= open("list.txt")
dict={}
i=[]
t=[]
lines = f.readlines()
for l in lines :
    if l[0]==0 : 
        ct=ct+1 
        b = ct
    
    elif (l[0]!= 0): 
        ind =l
      
    if ind not in dict: 
        dict[ind]=cnt
    t.append(b)
    i.append(dict[ind])
    cnt=cnt+1

plot(t,i,'.k')
xlabel('Time (ms)')
ylabel('Neuron index')

When I execute it i dont get any errors. But i dont get the desired output also. The IF statement inside the FOR loop was not executed. When i tried to debug the program using pdb, I get this.

(Pdb) from brian2 import *
(Pdb) import matplotlib
(Pdb) 
(Pdb) 
(Pdb) start_scope()
(Pdb) cnt=1
(Pdb) ct=0
(Pdb) f= open("list.txt")
(Pdb) dict={}
(Pdb) i=[]
(Pdb) t=[]
(Pdb) lines = f.readlines()
(Pdb) for l in lines :
*** SyntaxError: unexpected EOF while parsing
(Pdb)     if l[0]==0 : 
*** SyntaxError: unexpected EOF while parsing
(Pdb)         ct=ct+1 
(Pdb)         b = ct
*** The specified object '= ct' is not a function or was not found along sys.path.
(Pdb)     
*** The specified object '= ct' is not a function or was not found along sys.path.
(Pdb)     elif (l[0]!= 0): 
*** SyntaxError: invalid syntax
(Pdb)         ind =l
*** NameError: name 'l' is not defined
(Pdb)       
*** NameError: name 'l' is not defined
(Pdb)     if ind not in dict: 
*** SyntaxError: unexpected EOF while parsing
(Pdb)         dict[ind]=cnt
*** NameError: name 'ind' is not defined
(Pdb)     t.append(b)
*** NameError: name 'b' is not defined
(Pdb)     i.append(dict[ind])
*** NameError: name 'ind' is not defined
(Pdb)     cnt=cnt+1
(Pdb) 
(Pdb) plot(t,i,'.k')
[<matplotlib.lines.Line2D object at 0x7fd91dfab0b8>]
(Pdb) xlabel('Time (ms)')
Text(0.5,0,'Time (ms)')
(Pdb) ylabel('Neuron index')
Text(0,0.5,'Neuron index')

PLEASE HELP TO DEBUG THIS

MY INPUT IS A FILE. FILE CONTENT
0001
2000
2004
3000
3004
0002
2001
2010
3010
3011
0003
2020
3020
3031

[buran]

first of all, don't use dict as a variable name, it's a built-in function and using it as a variable name you overwrite it.
second, when you read from file, it will read string, so l[0]!= 0 will be true ('0' != 0). Probably that is why you don't get your expected result

[upasana]

first of all, don't use dict as a variable name, it's a built-in function and using it as a variable name you overwrite it. second, when you read from file, it will read string, so l[0]!= 0 will be true ('0' != 0). Probably that is why you don't get your expected result

Thank you for your suggestion. Can you please tell me how can i otherwise check whether the 0th element is 0 or not?

[buran]

you need to check it against str

l[0]!= '0':
    # do something
else:
    # do something ese

or

if l[0].startswith('0'):
    # do something if it start with 0
else:
    # do something else

note that your code has other problems too - e.g. there could be case when b is not defined on line #23 to name one...

[upasana]

you need to check it against str

l[0]!= '0': # do something else: # do something ese

or

if l[0].startswith('0'): # do something if it start with 0 else: # do something else

note that your code has other problems too - e.g. there could be case when b is not defined on line #23 to name one...

Thank you so much again... yea.. it does have that "name error". I have shared the pdb version also- shows other errors like "SyntaxError: unexpected EOF while parsing" . what should i do to rectify it?

[buran]

forget about pdb for now... resolve problems that raise when you run it.

[upasana]

forget about pdb for now... resolve problems that raise when you run it.

Thank you so much for your help. The code runs without any error and I get the desired output also. :D