# queryCSV.py
# FB - 201010111
# Query a CSV file.
# example CSV file: myData.csv
# id,code name,value
# 36,abc,7.6
# 40,def,3.6
# 9,ghi,6.3
# 76,def,99
# example query expression
query = 'id > 36 and code_name == "def" and value <= 100'
print 'Query:'
print query
print
import csv
csvData = csv.reader(open('myData.csv'))
csvTable = []
isHeader = True
for row in csvData:
if isHeader:
isHeader = False
headerRow = row
for i in range(len(headerRow)):
# replace spaces w/ underscores in column headers
headerRow[i] = headerRow[i].replace(' ', '_')
else:
csvTable.append(row)
# determine column types: string/int/float
colType = []
for i in range(len(headerRow)):
isFloat = True
isInt = True
for j in range(len(csvTable)):
try:
v = float(csvTable[j][i])
if not v == int(v):
isInt = False
except ValueError:
isFloat = False
isInt = False
colT = ''
if isInt:
colT = 'int'
elif isFloat:
colT = 'float'
else:
colT = 'string'
colType.append(colT)
# print headerRow[i], colT
# run the query
for j in range(len(csvTable)):
# assign the column variables
for i in range(len(headerRow)):
if colType[i] == 'string':
exec(headerRow[i] + '=' + '"' + csvTable[j][i] + '"')
elif colType[i] == 'float':
exec(headerRow[i] + '=' + 'float("' + csvTable[j][i] + '")')
elif colType[i] == 'int':
exec(headerRow[i] + '=' + 'int("' + csvTable[j][i] + '")')
# output the rows matching the query
if eval(query):
print headerRow
print csvTable[j]
print
Diff to Previous Revision
--- revision 3 2010-10-08 19:34:33
+++ revision 4 2010-10-12 00:08:22
@@ -1,5 +1,5 @@
# queryCSV.py
-# FB - 201010085
+# FB - 201010111
# Query a CSV file.
# example CSV file: myData.csv
@@ -10,7 +10,7 @@
# 76,def,99
# example query expression
-query = 'int(id) > 36 and code_name == "def" and float(value) <= 100'
+query = 'id > 36 and code_name == "def" and value <= 100'
print 'Query:'
print query
@@ -18,20 +18,56 @@
import csv
csvData = csv.reader(open('myData.csv'))
-rowNum = 0
+csvTable = []
+isHeader = True
for row in csvData:
- if rowNum == 0:
+ if isHeader:
+ isHeader = False
headerRow = row
- else:
- # assign the column variables
for i in range(len(headerRow)):
- # replace spaces w/ underscores
+ # replace spaces w/ underscores in column headers
headerRow[i] = headerRow[i].replace(' ', '_')
- exec(headerRow[i] + '=' + '"' +row[i] + '"')
- # output the rows matching the query
- if eval(query):
- print headerRow
- print row
- print
+ else:
+ csvTable.append(row)
- rowNum +=1
+# determine column types: string/int/float
+colType = []
+for i in range(len(headerRow)):
+ isFloat = True
+ isInt = True
+ for j in range(len(csvTable)):
+ try:
+ v = float(csvTable[j][i])
+ if not v == int(v):
+ isInt = False
+ except ValueError:
+ isFloat = False
+ isInt = False
+
+ colT = ''
+ if isInt:
+ colT = 'int'
+ elif isFloat:
+ colT = 'float'
+ else:
+ colT = 'string'
+ colType.append(colT)
+
+ # print headerRow[i], colT
+
+# run the query
+for j in range(len(csvTable)):
+ # assign the column variables
+ for i in range(len(headerRow)):
+ if colType[i] == 'string':
+ exec(headerRow[i] + '=' + '"' + csvTable[j][i] + '"')
+ elif colType[i] == 'float':
+ exec(headerRow[i] + '=' + 'float("' + csvTable[j][i] + '")')
+ elif colType[i] == 'int':
+ exec(headerRow[i] + '=' + 'int("' + csvTable[j][i] + '")')
+
+ # output the rows matching the query
+ if eval(query):
+ print headerRow
+ print csvTable[j]
+ print
