working on exercises

python/learnpython.org/Basics/chapter-05/README.md

@@ -0,0 +1,24 @@
+String Formatting
+
+Here are some basic argument specifiers you should know:
+
+%s - String (or any object with a string representation, like numbers)
+
+%d - Integers
+
+%f - Floating point numbers
+
+%.<number of digits>f - Floating point numbers with a fixed amount of digits to the right of the dot.
+
+%x/%X - Integers in hex representation (lowercase/uppercase)
+
+
+
+
+Exercise
+
+You will need to write a format string which prints out the data using: the following syntax: Hello John Doe. Your current balance is $53.44
+
+
+
+

python/learnpython.org/Basics/chapter-05/exercise.py

@@ -0,0 +1,5 @@
+balance = 53.44
+firstName = "John"
+lastName = "Doe"
+
+print("Hello %s %s. Your current balance is %.2f." % (firstName,lastName,balance))

python/learnpython.org/Basics/chapter-05/string-formatting.py

@@ -0,0 +1,7 @@
+firstName = "John"
+lastName = "Doe"
+yourAge = 35
+
+print ("Hello to you %s" % firstName, "%s!" % lastName, "\nYou are %d" % yourAge, "Years old")
+
+print ("%s is %d years old!" % (firstName,yourAge))

python/learnpython.org/Basics/chapter-06/README.md

@@ -0,0 +1,42 @@
+Basic String Operations
+
+
+Exercise
+
+Try to fix the code to print out the correct information by changing the string.
+
+
+s = "Hey there! what should this string be?"
+# Length should be 20
+print("Length of s = %d" % len(s))
+
+# First occurrence of "a" should be at index 8
+print("The first occurrence of the letter a = %d" % s.index("a"))
+
+# Number of a's should be 2
+print("a occurs %d times" % s.count("a"))
+
+# Slicing the string into bits
+print("The first five characters are '%s'" % s[:5]) # Start to 5
+print("The next five characters are '%s'" % s[5:10]) # 5 to 10
+print("The thirteenth character is '%s'" % s[12]) # Just number 12
+print("The characters with odd index are '%s'" %s[1::2]) #(0-based indexing)
+print("The last five characters are '%s'" % s[-5:]) # 5th-from-last to end
+
+# Convert everything to uppercase
+print("String in uppercase: %s" % s.upper())
+
+# Convert everything to lowercase
+print("String in lowercase: %s" % s.lower())
+
+# Check how a string starts
+if s.startswith("Str"):
+    print("String starts with 'Str'. Good!")
+
+# Check how a string ends
+if s.endswith("ome!"):
+    print("String ends with 'ome!'. Good!")
+
+# Split the string into three separate strings,
+# each containing only a word
+print("Split the words of the string: %s" % s.split(" "))

python/learnpython.org/Basics/chapter-06/exercise.py

@@ -0,0 +1,35 @@
+s = "Str thera! whatsome!"
+
+# Length should be 20
+print("Length of s = %d" % len(s))
+
+# First occurrence of "a" should be at index 8
+print("The first occurrence of the letter a = %d" % s.index("a"))
+
+# Number of a's should be 2
+print("a occurs %d times" % s.count("a"))
+
+# Slicing the string into bits
+print("The first five characters are '%s'" % s[:5]) # Start to 5
+print("The next five characters are '%s'" % s[5:10]) # 5 to 10
+print("The thirteenth character is '%s'" % s[12]) # Just number 12
+print("The characters with odd index are '%s'" %s[1::2]) #(0-based indexing)
+print("The last five characters are '%s'" % s[-5:]) # 5th-from-last to end
+
+# Convert everything to uppercase
+print("String in uppercase: %s" % s.upper())
+
+# Convert everything to lowercase
+print("String in lowercase: %s" % s.lower())
+
+# Check how a string starts
+if s.startswith("Str"):
+    print("String starts with 'Str'. Good!")
+
+# Check how a string ends
+if s.endswith("ome!"):
+    print("String ends with 'ome!'. Good!")
+
+# Split the string into three separate strings,
+# each containing only a word
+print("Split the words of the string: %s" % s.split(" "))

python/learnpython.org/Basics/chapter-06/strings.py

@@ -0,0 +1,45 @@
+aString = "Hello World!"
+
+print ("Use aString.index(\"LETTER\") to return the first time that letter appears")
+        
+print ("The first time o appears is at index : ", aString.index("o")) # returns what place in the string matches the specified character "o" in this case INDEX STARTS AT ZERO!!
+
+print ("L appears : ", aString.count("l"), "Times") # returns how many times the specified character appears in the string
+
+print ("\n\nTo return specific portions of a string use aString[start:stop]")
+print (aString[3:7]) # Will return from the index position 3-7 in the string.
+
+print (aString[0:5:2]) #This is stepping, meaning you want to only see every 2nd character.
+
+#
+print (aString[:-1:])
+
+print ("\n\nTo print a string backwords use this syntax print (aString[::-1])")
+print (aString[::-1])
+
+#to retrieve the last x amount of characters
+
+print (aString[-1:5]) #This will fetch the last 5 characters
+
+print ("\n\nTo retrieve a specified length, starting from the beginning of the file, use the syntax aString[:LENGTH]")
+print (aString[:5])
+
+print ("\n\n to retrieve a specified length, starting from the end of the file, use syntax aString[-5:]")
+print (aString[-5:])
+
+print ("\n\nTo retrieve the entire string, after a specified character, use syntax aString[4:] ")
+print (aString[4:])
+
+
+print ("There are also UPPER and LOWER functions for strings!")
+print (aString.upper())
+print (aString.lower())
+
+
+print ("\n\nWe can determine if a string starts or ends with a certain sequence by using: aString.startswith(\"\") and aString.endswith(\"\")")
+print (aString.startswith("Hello"))
+
+print ("\n\n You can split strings into multiple strings by using aString.split(\" \")")
+newString = aString.split(" ")
+print (newString)
+print ("It creates a new table, with each string as its entry or index")

python/learnpython.org/Basics/chapter-07/README.md

@@ -0,0 +1,60 @@
+Conditions
+
+The 'is' operator
+
+Unlike the double equals operator "==", the "is" operator does not match the values of the variables, but the instances themselves
+
+x = [1,2,3]
+y = [1,2,3]
+print(x == y) # Prints out True
+print(x is y) # Prints out False
+
+
+The "in" operator
+
+The "in" operator could be used to check if a specified object exists within an iterable object container, such as a list:
+name = "John"
+if name in ["John", "Rick"]:
+    print("Your name is either John or Rick.")
+
+
+Boolean operators
+
+The "and" and "or" boolean operators allow building complex boolean expressions, for example:
+name = "John"
+age = 23
+if name == "John" and age == 23:
+    print("Your name is John, and you are also 23 years old.")
+
+if name == "John" or name == "Rick":
+    print("Your name is either John or Rick.")
+
+
+
+Exercise
+
+Change the variables in the first section, so that each if statement resolves as True.
+
+# change this code
+number = 10
+second_number = 10
+first_array = []
+second_array = [1,2,3]
+
+if number > 15:
+    print("1")
+
+if first_array:
+    print("2")
+
+if len(second_array) == 2:
+    print("3")
+
+if len(first_array) + len(second_array) == 5:
+    print("4")
+
+if first_array and first_array[0] == 1:
+    print("5")
+
+if not second_number:
+    print("6")