python print format and line breaking

Question

I have this loop:

for n in range(101):
 money_growth = A*(1 + p/100)**n
 print "%d Euro after %3d year[s] with \
 interest of %0.2f will be %0.2f" %(A, n, p, money_growth)

I break the line with \ in front of print statement but it will extra tab due to the loop intention:

00 year[s] with interest of 0.05

the only solution I found was doing t this way:

 for n in range(101):
 money_growth = A*(1 + p/100)**n
 print "%d Euro after %3d year[s] with \
 interest of %0.2f will be %0.2f" %(A, n, p, money_growth)

but It destroy the readability somehow is there any better way?

Answer 1

You may use implicit string concatenation by breaking the string as:

for n in range(101):
 money_growth = A*(1 + p/100)**n
 print "%d Euro after %3d year[s] with" \
 "interest of %0.2f will be %0.2f" %(A, n, p, money_growth)

Answer 2

Using string format and print with brackets () for Python 3 compitability. We could also use indexes if we want to repeat a string.

A,p,n = 1,1,1
string = "{} Euro after {:>3} year[s] with interest of {} will be {:.2f}"
#string = "{0} Euro after {1:>3} year[s] with interest of {2} will be {3:.2f}"
for n in range(101):
 money_growth = A*(1 + p/100)**n
 print(string.format(A, n, p, money_growth))

or: we could use list comprehension and join the list print items with row breaks.

A,p,n = 1,1,1
string = "{} Euro after {:>3} year[s] with interest of {} will be {:.2f}"
output = [string.format(A, n, p, A*(1 + p/100)**n) for n in range(101)]
print('\n'.join(output))

This is very powerful way to print strings, the options are endless and I always learn something new when I look through the docs. For instance you can use this to convert numbers to Hex format.

rgb = (0,100,200)
string = "#"+"{:02x}"*3
print(string.format(*rgb))

Returns:

#0064c8

Answer 3

for n in range(101):
 money_growth = A*(1 + p/100)**n
 print("{:d} {} {:3d} {} {} {:.2f} {} {:.2f}".format(
 A, "Euro after", n, "years[s]","with interest of", p, "will be", money_growth
 ))

A good way to avoid this is to use string formatting function. You can format it in chain fashion.

Answer 4

Place the format string outside your loop:

s = "%d Euro after %3d year[s] with interest of %0.2f will be %0.2f"
for n in range(101):
 money_growth = A*(1 + p/100)**n
 print s % (A,n,p,money_growth)