Page 257 - Computer Science Class 11 With Functions
P. 257
Program 10.13 To display the inverted isosceles triangular pattern of a symbol.
01 def invertedIsoTriangle(nRows, symbol):
02 '''
03 Objective: To display an inverted isosceles triangular pattern
04 Inputs:
05 nRows : number of rows
06 symbol: symbol to be printed
07 Return value: None
08 '''
09 #Approach: In each line,
10 # first print enough blanks, then enough symbols
11
12 nSpaces = 0
13 nSymbols = 2 * nRows - 1
14
15 for i in range(nRows):
16 print(' ' * nSpaces, end = '')
17 print(symbol * nSymbols)
18 nSpaces = nSpaces + 1
19 nSymbols = nSymbols - 2
20 invertedIsoTriangle(6, '*')
Sample Output:
***********
*********
*******
*****
***
*
Fig 10.6: Inverted Isosceles Triangle
Next, let us write a function to print an isosceles triangle using a given symbol (say, symbol). Fig 10.7 shows an
th
isosceles triangle comprising six rows using asterisks. Note that the last row (6 row) does not have any leading
th
th
spaces, 5 row has one leading space, the 4 row has two leading spaces, and so on. Finally, the first row has 5 (=6-1)
th
spaces. Thus, i row has nRows-i leading spaces. Furthermore, the first row has one asterisk, the second row has
th
3 asterisks, and so on. Finally, the sixth row has 11 (=6×2-1) asterisks. Thus, i row has 2×i-1 asterisks. Now we are
ready to write a function to display an isosceles triangle.
Program 10.14 Write a function isoscelesTriangle(nRows,symbol) to display the isosceles triangular pattern
of a symbol.
01 def isoscelesTriangle(nRows, symbol):
02 '''
03 Objective: To display an isosceles triangular pattern of a symbol
04 Inputs:
05 nRows : number of rows
06 symbol: symbol to be printed
07 Return value: None
08 '''
09 #Approach: In each line,
10 # first print enough blanks, then enough symbols
11
12 nSpaces = nRows-1
13 nSymbols = 1
14 for row in range(1, nRows + 1):
15 print(' ' * nSpaces, end = '')
16 print(symbol * nSymbols)
Looping in Python 255

