Learning Python: Introductory Excercises

These are rudimentary functions created in Python, working through the exercises in Computational Statistics in Python from Duke.


 def power_function(num, power):  
   """Funcion to caculate power, number ** power."""  
   return num**power  
   
 def fizz_buzz(begin, end):  
   """Write a program that prints the numbers from 1 to 100.  
   But for multiples of three print “Fizz” instead of the number  
   and for the multiples of five print “Buzz”.  
   For numbers which are multiples of both three and five print “FizzBuzz"""  
   for i in range(begin, end):  
     if i%3 == 0 & i%5 == 0:  
       print("FizzBuzz")  
     elif i%5 == 0:  
       print("Buzz")  
     elif i%3 == 0:  
       print("Fizz")  
     else:  
       print(1)  
   
 def euclidean(UPoint, VPoint, ShortCalc):  
   """Write a function that calculates and returns the euclidean distance   
   between two points u and v, where u and v are both 2-tuples (x,y).   
   For example, if u=(3,0) and v=(0,4) the function should return 5."""  
   try:  
     if ShortCalc == False:  
       hyp = UPoint[0]**2 + VPoint[1]**2  
       return hyp**.5  
     elif ShortCalc == True:  
       return math.hypot(UPoint[0], VPoint[1])  
   except:  
     return 0  
   
 def CountCharacters(someString):  
    """Using a dictionary, write a program to calculate the number times   
    each character occurs in the given string s. Ignore differneces in   
    capitalization - i.e ‘a’ and ‘A’ should be treated as a single key.   
    For example, we should get a count of 7 for ‘a’."""  
    arr = list(someString.lower())  
    arrUnique = dict.fromkeys(set(arr), 0)  
    for item in arrUnique:  
      arrUnique[item] = arr.count(item)  
    return arrUnique  
   
 def CountCharactersAlt(someString):  
    """Using a dictionary, write a program to calculate the number times   
    each character occurs in the given string s. Ignore differneces in   
    capitalization - i.e ‘a’ and ‘A’ should be treated as a single key.   
    For example, we should get a count of 7 for ‘a’."""  
    newDict = {}  
    for item in list(someString.lower()):  
      try:  
        val = newDict.get(item)  
        newDict[item] = val + 1  
      except:  
        newDict[item] = 1  
    return newDict  
   
 def CountCharactersAlt2(someString):  
    """Using a dictionary, write a program to calculate the number times   
    each character occurs in the given string s. Ignore differneces in   
    capitalization - i.e ‘a’ and ‘A’ should be treated as a single key.   
    For example, we should get a count of 7 for ‘a’."""  
    newDict = {}  
    for item in someString.lower():  
      newDict[item] = newDict.get(item, 0) + 1  
    return newDict  
   
 #import string  
 def Sliding_Windows_Percentage(someString, findThis):  
    """Write a program that finds the percentage of sliding windows   
    of length 5 for the sentence s that contain at least one ‘a’.   
    Ignore case, spaces and punctuation. For example, the first   
    sliding window is ‘write’ which contains 0 ‘a’s, and the second   
    is ‘ritea’ which contains 1 ‘a’."""  
    exclude = set(string.punctuation)  
    out = ''.join(ch for ch in someString if ch not in exclude)  
    found_Counter = 0  
    for i in range(0, len(out)-4):  
      if findThis in out[i: i+4]:  
        found_Counter += 1  
    return found_Counter / (len(out)-4)  
   


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