def filterBadValues(in_filename, out_filename, keys):
print 'filterBadValues', in_filename, out_filename, keys
fin = open(in_filename, 'rt')
fout = open(out_filename, 'wt')
header = csv.readCsvLine(fin)
csv.writeCsvRow(fout, header)
print header
data = csv.readCsvGen(fin)
column_index = dict(zip(keys, [header.index(k) for k in keys]))
num_rows = 0
num_bad = 0
for row in data:
bad_row = False
for k in keys:
val = float(row[column_index[k]])
if val < 0:
bad_row = True
num_bad += 1
if not bad_row:
csv.writeCsvRow(fout, row)
num_rows += 1
fin.close()
fout.close()
print in_filename, num_rows, 'rows'
print out_filename, num_rows - num_bad, 'rows'
def sampleCsv(in_filename, out_filename, ratio):
""" Sample a csv file. """
print 'sampleCsv', in_filename, out_filename, ratio
fin = open(in_filename, 'rt')
fout = open(out_filename, 'wt')
header = csv.readCsvLine(fin)
print 'header:', header
csv.writeCsvRow(fout, header)
data = csv.readCsvGen(fin)
num_sampled = 0
for irow,row in enumerate(data):
if irow % 100000 == 0:
print (irow,num_sampled),
if num_sampled < ratio * irow:
csv.writeCsvRow(fout, row)
num_sampled += 1
print
fin.close()
fout.close()
print in_filename, irow, 'rows'
print out_filename, num_sampled, 'rows'
if True:
fin = open(out_filename, 'rt')
header = csv.readCsvLine(fin)
data = csv.readCsvGen(fin)
for irow,row in enumerate(data):
if len(row) != len(header):
print irow, len(row), row, len(header), header
assert(len(row) == len(header))
fin.close()
