[Numpy-discussion] subset of array - statistics

[bevan]

Hello,

I am new to the world of Python and numpy but am very excited by what I have 
seen so far.

I have been playing around with some rainfall data.  The data is daily rainfall 
for a period, say 30 years in the form:
Year  Month  JulianDay  Rain (mm)
1970  1       1          0.0
1970  1       2          0.5
.................................
2008  3      65          2.5

I have successfully imported the data into lists and then created a single 
array from the lists.

I can get the rainfall total over the entire period using:

raindata = numpy.array([yr,mth,jd,rain_mm],dtype=float)
print data[3,:].sum(axis=0)
 or
raindata= numpy.rec.fromarrays
([yr,mth,jd,rain_mm],names='year,month,julian,rain_mm')
print raindata.rain_mm.sum(axis=0)

But what i would like to do is get an average rainfall for each month and also 
the ability to get rainfall totals for any month and Year

I thought it would be straight forward but have not gotten my head around it 
yet.  Thanks for your help and thakns to the people eho have develoepd and 
maintain numpy & python