get_filename.py

get_filename.py

@@ -0,0 +1,63 @@
+# Python 2.7
+# prompt user for file of specific type(s).
+# 11/01/13 sebastian raschka
+
+import os.path
+
+def get_filename(file_type):
+    '''repeatedly prompts user for a file of specific type.
+       arguments:
+           file_type: list with accepted file types as strings.
+       returns:
+           (string): absolute path to the specified input file.
+    '''
+    while True:
+        print "\n\nplease enter a file name, \nor type --help to get"\
+                " a list of the accepted file formats"
+        file_name = raw_input(": ")
+        if file_name == "--help":
+            print "\naccepted file format(s): ",
+            for f in file_type:
+                print f,
+            continue        
+        if not os.path.isfile(file_name):
+            print "\n\nsorry, this file doesn't exist. please try again.\n"
+            continue
+        if not (file_name.split(".")[-1] in file_type):
+            print "\nplease provide a file in correct format."
+            continue
+        break
+    return os.path.abspath(file_name)
+
+#get_filename(["txt", "doc"])
+
+
+# ===========================
+# EXAMPLE
+# ===========================
+
+'''
+[bash]~/Desktop >python get_filename.py 
+
+
+please enter a file name, 
+or type --help to get a list of the accepted file formats
+: --help
+
+accepted file format(s):  txt doc 
+
+please enter a file name, 
+or type --help to get a list of the accepted file formats
+: test.tx 
+
+
+sorry, this file doesn't exist. please try again.
+
+
+
+please enter a file name, 
+or type --help to get a list of the accepted file formats
+: test.txt
+[bash]~/Desktop >
+'''
+