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I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
The String formatter
String Handling example from a Well House Consultants training course
More on String Handling [link]

This example is described in the following article(s):
   • Python string formatting - the move from % to str.format - [link]

Source code: strf Module: Y108
# The String formatter

# New in Python 2.6, and becoming THE standard in Python 3.0 ...
# a replacement for the "%" string format operator

# (a) - deciding what to fill in ....

one = "This is a test".format()
two = "This is a {} test".format("second")
three = "This is a {0} test".format("third")
four = "This is a {which} test".format(which = "fourth")

mycollection = ["fifth","sixth","final"]
five = "This is a {0[2]} initial test".format(mycollection)

print(one)
print(two)
print(three)
print(four)
print(five)

print() ; # a blank line

# (b) - deciding how to format it ...

# field specification for formatting - examples using floating point

value = -1.0/7.0
print( "The raw value is",value)

seven = "The value is {}".format(value) ; # default - 14 places
eight = "The value is {:f}".format(value) ; # default float format - 7 places
nine = "The value is {:.2f}".format(value) ; # 2 decimal places
ten = "The value is {:10.2f}".format(value) ; # min field width 10, 2 decimal places
print(seven)
print(eight)
print(nine)
print(ten)

print() ; # a blank line

# (c) - deciding how to align it and fill it

eleven = "The value is {:<10.2f} rounded to 2 decimal places".format(value) ; # left justified
twelve = "The value is {:>10.2f} rounded to 2 decimal places".format(value) ; # right justified
thirteen = "The value is {:^10.2f} rounded to 2 decimal places".format(value) ; # centred
fourteen = "The value is {:*>10.2f} rounded to 2 decimal places".format(value) ; # leading * filled
fifteen = "The value is {:*=10.2f} rounded to 2 decimal places".format(value) ; # leading * filled after sign

print(eleven)
print(twelve)
print(thirteen)
print(fourteen)
print(fifteen)

print() ; # a blank line

# Conversion types - for FLOATING POINT NUMBERS: e E f F g G n % and none .
# e - exponential. f - fixed. g - general (use best choice of e or f based on number value.
# E F G are like e f g but capitalise letter E when used.
# n like g but considers locale. % makes number into a percentage and uses f formatting.

# Integer conversion types ...

demovals = [14,120,1642,-9]

sixteen = "In binary {0[0]:b} and {0[1]:^5b} and {0[2]:<15b} and {0[3]:8b}".format(demovals)
seventeen = "In octal {0[0]:o} and {0[1]:^5o} and {0[2]:<15o} and {0[3]:8o}".format(demovals)
eighteen = "In decimal {0[0]:d} and {0[1]:^5d} and {0[2]:<15d} and {0[3]:8d}".format(demovals)
nineteen = "In hexadecimal {0[0]:x} and {0[1]:^5x} and {0[2]:<15x} and {0[3]:8x}".format(demovals)
twenty = "In heXadecimal {0[0]:X} and {0[1]:^5X} and {0[2]:<15X} and {0[3]:8X}".format(demovals)

print(sixteen)
print(seventeen)
print(eighteen)
print(nineteen)
print(twenty)

print() ; # a blank line

""" Sample Output

WomanWithCat:y108 grahamellis$ python3 strf
This is a test
This is a second test
This is a third test
This is a fourth test
This is a final initial test

The raw value is -0.14285714285714285
The value is -0.14285714285714285
The value is -0.142857
The value is -0.14
The value is -0.14

The value is -0.14 rounded to 2 decimal places
The value is -0.14 rounded to 2 decimal places
The value is -0.14 rounded to 2 decimal places
The value is *****-0.14 rounded to 2 decimal places
The value is -*****0.14 rounded to 2 decimal places

In binary 1110 and 1111000 and 11001101010 and -1001
In octal 16 and 170 and 3152 and -11
In decimal 14 and 120 and 1642 and -9
In hexadecimal e and 78 and 66a and -9
In heXadecimal E and 78 and 66A and -9
WomanWithCat:y108 grahamellis$ python2 strf
This is a test
This is a second test
This is a third test
This is a fourth test
This is a final initial test
()
('The raw value is', -0.14285714285714285)
The value is -0.142857142857
The value is -0.142857
The value is -0.14
The value is -0.14
()
The value is -0.14 rounded to 2 decimal places
The value is -0.14 rounded to 2 decimal places
The value is -0.14 rounded to 2 decimal places
The value is *****-0.14 rounded to 2 decimal places
The value is -*****0.14 rounded to 2 decimal places
()
In binary 1110 and 1111000 and 11001101010 and -1001
In octal 16 and 170 and 3152 and -11
In decimal 14 and 120 and 1642 and -9
In hexadecimal e and 78 and 66a and -9
In heXadecimal E and 78 and 66A and -9

WomanWithCat:y108 grahamellis$

"""

Learn about this subject
This module and example are covered on the following public courses:
 * Learning to program in Python
 * Python Programming
 * Intermediate Python
Also available on on site courses for larger groups

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Other Examples
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