Update IV Functions and Automation.py

Author: ortizfram

Introduction to Bash Scripting/IV Functions and Automation.py

@@ -75,3 +75,73 @@
 
 repl:~/workspace$ bash script.sh
 Fri
+
+"""
+*** Scope in programmming
+    >>>>>> 'Global' : accessible anywhere in the program
+    >>>>>> 'Local' : accessible only in ceratain part of the program; like inside a for 
+    
+    *** All vars in Bash are GLOBALly BY default   
+"""
+
+"""
+### A percentage calculator
+
+Instructions
+
+- Create a function called return_percentage using the function-word method.
+- Create a variable inside the function called percent that divides the first argument fed into the function by the second argument.
+- Return the calculated value by echoing it back.
+- Call the function with the mentioned test values of 456 (the first argument) and 632 (the second argument) and echo the result.
+"""
+# Create a function 
+function return_percentage () {
+
+  # Calculate the percentage using bc
+  percent=$(echo "scale=2; 100 * $1 / $2" | bc)
+
+  # Return the calculated percentage
+  echo $percent
+}
+
+# Call the function with 456 and 632 and echo the result
+return_test=$(return_percentage 456 632)
+echo "456 out of 632 as a percent is $return_test%"
+
+
+repl:~/workspace$ bash script.sh
+456 out of 632 as a percent is 72.15%
+
+"""
+### Create a function with a local base variable
+
+An array of numbers you can use for a test of your function would be the daily sales in your organization this week (in thousands):
+
+14 12 23.5 16 19.34 which should sum to 84.84
+
+Instructions
+
+- Create a function called sum_array and add a base variable (equal to 0) called sum with local scope. You will loop through the array and increment this variable.
+- Create a FOR loop through the ARGV array inside sum_array (hint: This is not $1! but another special array property) and increment sum with each element of the array.
+- Rather than assign to a global variable, echo back the result of your FOR loop summation.
+- Call your function using the test array provided and echo the result. You can capture the results of the function call using the shell-within-a-shell notation.
+"""
+# Create a function with a local base variable
+function sum_array () {
+  local sum=0
+  # Loop through, adding to base variable
+  for number in "$@"
+  do
+    sum=$(echo "$sum + $number" | bc)
+  done
+  # Echo back the result
+  echo $sum
+  }
+# Call function with array
+test_array=(14 12 23.5 16 19.34)
+total=$(sum_array "${test_array[@]}")
+echo "The total sum of the test array is $total"
+
+
+repl:~/workspace$ bash script.sh
+The total sum of the test array is 84.84