4-simpleGrid.py

# define the width and height of the new page
#       w     h
newPage(1000, 1000)

# define x and y as where we start? (0, 0) is in the bottom left
x = 0
y = 0

# define how many rows and columns
rows = 10
cols = 10

# define the width and height of each unit of the grid
gridWidth = 100
gridHeight = 100

# define the width and height of the shape we will draw in that grid
shapeWidth = 100
shapeHeight = 100

# ok it’s time to loop
# first we will loop through each row
# and then WITHIN that loop we will loop through each column
# for theThing in theRangeOfThings
for row in range(rows):
    # everything indented this much runs once for each row
    for col in range(cols):
        # everything indented this much 
        # runs once for each column 
        # within each row (one grid unit)   
        #    x   y   w    h
        oval(x, y, shapeWidth, shapeHeight)
        x += gridWidth
    # we are OUTDENTED, which means we are back 
    # to code that only runs once per row
    # now that we’ve reached the end of the row
    # we want to advance y to move us up to the next row
    y += gridHeight
    # and we want to return x to its original position
    # (a carriage return, essentially)
    x -= cols*gridWidth