I will post what I currently have and also the tests for it. Unfortunately it randomly fails some tests so I was wondering if anyone could help.

def sumDigits(s): '''Input s is a string. The returned value should be the sum of all numerical digits in s. In addition, if the first non-empty char of s is a minus sign, then the returned value should add a minus sign to the sum. E.g., sumDigits('A33$%4C*+D') should return 10, sumDigits('-+z33$%4-D') and sumDigits(' -A+3-3-4*D') should both return -10. That is, minus sign matters only when it is the first non-empty char. You may need to look up s.isdigit(), s.lstrip(' ') from help(str). ''' r = 0 f = 1 flag = 0 for i in s: if i.isdigit(): r = r+ int(i) if flag == 0: if i =='-': f = -1 flag = 1 sumofdigits= f*r return sumofdigits

###################################################################### if __name__=='__main__':

import numpy as np import string, random

nondigits = string.ascii_letters + ' ' + string.punctuation

DEBUG = True #DEBUG = False #uncomment to show more screen output

repeat=200 #arvect=np.random.randn(repeat,1) arvect=np.random.normal(10**16, 10**17, (repeat,1)) arrint=[int(x*10) for x in arvect]

TEST=[]; tsum={}; ysum={} for i in range(len(arrint)): if arrint[i] >= 0: sloc=0 for j in str(arrint[i]): sloc+=int(j) #end for j tsum[i]=sloc else: sloc=0 for j in str(arrint[i])[1:]: sloc+=int(j) #end for j tsum[i]=-sloc #end if

s1=str(arrint[i]) s2=[s1[0]] for j in s1[1:]: s2.append(j) s2.append(random.choice(nondigits)) if i%2 == 0: s = ' ' + ''.join(s2) else: s = ' -/ ' + ''.join(s2) if tsum[i]>0: tsum[i]=-tsum[i]

if DEBUG: print('s=',s)

ysum[i]=sumDigits(s) if tsum[i] == ysum[i]: TEST.append(True) else: TEST.append(False) #end for i

if all(TEST): print(" Great, you passed {} tests for Problem 3! ".format(repeat)) else: print(" *** {} tests failed for Problem 3. Need more debugging. ".format(len([x for x in TEST if x==False])))

Prob. 3 Develop a function that meets the requirement in the document string of sumDigits: 1 def sumDigits (s): 'Inputsisastring.The returned value should be the sum of all numerical digits in s In addition if the first non-empty char ofs is a minus sign then the returned value should add a minus sign to the sum E.g., sumDigits("A33S%4C++D ') should return 10, sunn Digits('-+z33S%4-D') 6 and sunn Digits (' -A+3-3-4D') should both return -10 That is minus sign matters only when it is the first non-empty char You may need to look up s.isdigitO,s.lstrip() from help (str) 10