Read and count

[Val Krem]

Hi all,

I am a new learner about python (moving from R to python) and trying  read and count the number of observation  by year for each city.


The data set look like
city year  x 

XC1 2001  10
XC1   2001  20
XC1   2002   20
XC1   2002   10
XC1 2002   10

Yv2 2001   10
Yv2 2002   20
Yv2 2002   20
Yv2 2002   10
Yv2 2002   10

out put will be

city
xc1  2001  2
xc1   2002  3
yv1  2001  1
yv2  2002  3


Below is my starting code
count=0
fo=open("dat", "r+")
str = fo.read();
print "Read String is : ", str

fo.close()


Many thanks