Formated Output

Print

print( value1, ..., sep=' ', end='\n', file=sys.stdout, flush=False)

with print you can output any number of arguments separated by commas

import sys
a = 3.123
print("a =", a)
# a: 3.123
print("a = \n", a)
# a =
#  3.123

with the argument sep you can change the separator that is output between the values:

print("a", "b")
# a b

print("a", "b", sep='')
# ab

print(194, 201, 38, 74, sep='.')
# 194.201.38.74

print("a", "b", sep=":)")
# a:)b

after the output python ends with a newline:

for i in range(3):
    print(i)
# 0
# 1
# 2

you can change the default ("\n") using end=" "

for i in range(3):
    print(i, end=" ")
# 0 1 2


for i in range(3):
    print(i, end=" :) ")
# 0 :) 1 :) 2 :)

using file you can output in to a file

fh = open("formatted_output/date.txt", "w")
print("42", file=fh)
fh.close()

it's also possible to output into the default error channel:

print("Error: 42", file=sys.stderr)
# Error: 42

C-Style Formating

info

is seen as a deprecated and bad style in python

print("some value: %4d, another: %3.1f" % (123, 1234.042))

Output:

some value: 123, another: 1234.0

Placeholder	Meaning
d/i	signed integer (integer, decimal)
o	unsigned integer in octal format
u	absolute otherwise like a signed integer
x	unsigned integer (hexadecimal)
X	unsigned integer (hexadecimal), uppercase
e	floating point numbers (exponential format)
E	like e but uppercase for exponent "e".
f	fixed point displays the number as a fixed point number
F	like f but nan is displayed as NAN
g	g corresponds to either e or f this is decided automatically depending on the size of the value and the given precision
G	G is analogous to g but it corresponds to either E or f
c	one character
s	a string any python elements are converted to a string using str()
%	no argument conversion takes place, a "% sign" is given

| Flag | Meaning | | ---- | -------------------------------------------------------------------------- | ------------------------------------------------------------------ | | # | if this character is used with o,x or X the respective value | is provided with the corresponding following prefix 0, 0o,0x or 0X | | 0 | the result of the conversion is padded with zeros | | - | the result of the conversion is left-justified | | | if no sign is specified, a blank character is placed in front of the value | | + | the result will be signed (+ or -) this flag overwrites a "space" flag |

Python-Method

the format syntax looks like this:

template.formate(p0, p1, ..., k0=v0, k1=v1, ...)

"first argument: {0}, second: {1}".format(47, 11)
# 'first argument: 47, second: 11'

"first argument: {1}, second: {0}".format(47, 11)
# 'first argument: 11, second: 47'

"first argument: {1:3d}, second: {0:7.2f}".format(47.42, 11)
# 'first argument:  11, second:   47.42'

"first argument: {}, second: {}".format(47, 11)
# 'first argument: 47, second: 11'

arguments can be used multiple times:

"first argument: {0:6.2f}, second: {0:6.3f}".format(1.4148)
# 'first argument:   1.41, second:  1.415'

this method also works:

"first argument: {a:5d}, second: {p:8.2f}".format(a=458, p=59.058)
# "first argument: {0:6.2f}, second: {0:6.3f}".format(1.4148)

with the .format method you can output data flush left (<) or flush right (>)

"{0:<20s} {1:6.2f}".format("something and something else:", 3.69)
# "something and something else:            3.69"

"{0:>20s} {1:6.2f}".format("something and something else:", 3.69)
# "         something and something else:   3.69"

"{0:>20s} {1:6.2f}".format("something & lorem ipsum:", 3.99)
# "         something & lorem ipsum:   3.99"

"{0:<20s} {1:6.2f}".format("something & lorem ipsum:", 3.99)
# "something & lorem ipsum:            3.99"

"{0:<20} {1:6.2f}".format("something & lorem ipsum:", 3.99)
# "something & lorem ipsum:            3.99"

"{0:>20} {1:6.2f}".format("something & lorem ipsum:", 3.99)
# "         something & lorem ipsum:   3.99"

| Option | Meaning | | ------ | ---------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------- | | '<' | field is left-justified within the existing space (strings are left-justified by default) | | '>' | field is output right-justified within the existing space (numeric values are output right-justified by default) | | '=' | padding characters are introduced between the sign, if a sign is output, and the actual | beginning of the digit of a number so that fields of the type '+00000420' can be output (can only be applied to numeric values) | | '^' | a field is output centered within the available space |

works only with numerical!!:

Option	Meaning
'+'	sign should always be output, regardless of whether the number is positive or negative.
'-'	sign should only be used for negative numbers
space	instead of a "+", positive numbers are preceded by a " " space. negative numbers are preceded by a minus sign "-".

String Literals

formatted string literals are strings preceded by an f they contain escaping fields that are evaluated for runtime and formatted according to the format rules

animal = "Dog"
height = 187.4
f"Animal: {animal}, Height: {height:6.2f}"
# 'Animal: Dog, Height: 187.40'

width, precision = 10, 3
x = 123.4238
f"Value: {x:{width}.{precision}}"
# 'Value:   3.69e+02'

Dictionaries

capital_country = {
    "united States": "Washington",
    "canada": "ottawa",
    "germany": "Berlin",
    "France": "Paris",
    "United Kingdom": "london",
    "switzerland": "Bern",
    "austria": "vienna",
}

print("countries and their capitals ")
for c in capital_country:
    print("{country}: {capital}".format(country=c, capital=capital_country[c]))

countries and their capitals
united States: Washington
canada: ottawa
germany: Berlin
France: Paris
United Kingdom: london
switzerland: Bern
austria: vienna

you can also use the dictionary directly in the call to the format method (the ouput is the same)

print("countries and their capitals:")
for c in capital_country:
    format_string = c + ": {" + c +"}"
    print(format_string.format(**capital_country))

Local Variables

locals is a function that returns a dictionary with the locally defined names and their current values

a = 42
b = 123
def f(): return 42


locals()
# a lot of text best use the function yourself


print("a={a}, b={b} and f={f}".format(**locals()))
# a=42, b=123 and f=<function f at 0x…>

Print​

C-Style Formating​

Python-Method​

String Literals​

Dictionaries​

Local Variables​