Hello I am doing a python turtle assignment and I wanted to

Hello, I am doing a python turtle assignment, and I wanted to know if I\'m on the right track.

Assignment Overview

In this assignment you will write a program to have a turtle follow commands given in a text file called moves.txt. The file will contain one command per line. There will be one of these three commands on each line: goto, jumpto, or color. They will be formatted as follows:

goto # x-coordinate #y-coordinate

jumpto #x-coordinate #y-coordinate

color

For goto and jumpto, the command and coordinates will be separated by #; color is a command itself. It is a legitimate instruction if there are spaces between fields on a line. For example,

     goto     #    45    #   100    

is a valid input

Here is how the commands work:

If the command is goto #x #y, then the turtle will go to the point (x,y) drawing a line as it moves.

If the command is jumpto #x #y, then the turtle will go to the point (x,y) without drawing a line. (remember penup() )

If the command is color, turtle will generate a random color and set its color to the new color so next drawing will be in that color.

Note: The commands goto, jumpto, and color can be upper or lowercase.

Input validation

In this program you will also validate the input from the file. That is, you will check whether the “input” that is the instruction from the file is valid or not. If it is an invalid instruction, then the program will append the line number to a list, skip the line and proceed with the next line.

When the program ends, print the list of invalid line numbers on the shell screen.

Some examples of invalid inputs:

go to #30#40       (go to is not a valid command)

color #30 #40      (color cannot be followed by non-white-space character)

jumpto #a2#34    (a2 is not a valid integer)

goto 30 #40          (need a separator before 30)

goto # # 40           (coordinate missing)

jumpto #30            (coordinate missing)

goto #30 #40 67    (not a valid coordinate)

goto #30#40#60    (too many coordinates)

Think about other possible mistakes or invalid inputs in the file and append line numbers in the list.

Start with implementing the goto#x#y command. First make sure that it works with valid input. For example if oves.txt has the following, then turtle should draw a square on the screen.

goto #0   #100

goto # 100 #100

goto #100    #0

goto #0 #   0

This is the code that I have thus far:

#!/usr/bin/python

fo = open(\"moves.txt\", \"r\")

lst = []

lin_num = 0

lines = fo.readlines()

for line in lines:

   lin_num = lin_num+1

   line = line.split(\'\ \')

   characters = line[0].split(\"#\")

   chars = []

   for character in characters:

       chars.append(character.split(\" \")[0])

   if chars:

       if str(chars[0]) == \'goto\' or str(chars[0]) == \'jumpto\':

           print chars[0]

           if len(chars) == 3:

               try:

                   int(str(chars[1]))

                   int(str(chars[2]))

               except ValueError:

                   lst.append(lin_num)

           else:

               lst.append(lin_num)

       elif chars[0] == \'color\':

           if len(chars) != 1:

               lst.append(lin_num)

       else:

           lst.append(lin_num)

   else:

       lst.append(lin_num)                                 

print \"Invalid Lines are:\"

for line in lst:

   print line

Solution

Your algo looks fine...

Other algo should be like this

Read each file till the end of file

Get first line

Remove all blank space from line

Get string till\'#\' character or up to last character

if string is color than it should be last character in line

else if string is \'goto\' or \'jumpto\' then parse further line

     Get string till 2nd \'#\'

     if extracted string is number then

           extract remaining string

           if remaining string is again a number then this is a correct line

     otherwise line is wrong