Creating implementation for idiom 348 : Convert a Decimal value into a Fraction

Idiom

# 348 Convert a Decimal value into a Fraction

Created by

Lead paragraph

Parse a number, a, into a fraction, f.

For example, 1.23 is `1 23/100`.

https://en.wikipedia.org/wiki/Decimal
https://en.wikipedia.org/wiki/Fraction

New implementation

Language

Imports

Code

Documentation URL

Original attribution URL

Online runnable demo

Username

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating material.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations

#include <cmath>
#include <iostream>
#include <numeric>
#include <regex>

using namespace std;
string s {to_string(a)}, f;
regex p {"\\."};
sregex_token_iterator r {
    begin(s), end(s), p, -1
};
int i {stoi(*r)}, n {stoi(*++r)},
    d {int(pow(10, r->length()))},
    v {gcd(n, d)};
if (v) {
    n /= v;
    d /= v;
}
if (not n) f = to_string(i);
else {
    f = to_string(n) + '/' + to_string(d);
    if (i) f = to_string(i) + ' ' + f;
}

let s = a.toString(), f,
    [x, y] = s.split('.'),
    i = parseInt(x), n = parseInt(y),
    d = Math.pow(10, y.length),
    gcf = (a, b) => !b ? a : gcf(b, a % b),
    v = gcf(n, d)
if (v) {
    n /= v;
    d /= v;
}
if (!n) f = i.toString()
else {
    f = `${n}/${d}`
    if (i) f = `${i} ${f}`
}

import static java.lang.Integer.parseInt;
import static java.lang.Math.pow;
import static java.lang.String.valueOf;

String s[] = valueOf(a).split("\\."), f;
int i = parseInt(s[0]), n = parseInt(s[1]),
    d = (int) pow(10, s[1].length()), v;
record GCF() {
    static int of(int a, int b) {
        return b == 0 ? a : of(b, a % b);
    }
}
if ((v = GCF.of(n, d)) != 0) {
    n = n / v;
    d = d / v;
}
if (n == 0) f = valueOf(i);
else if (i != 0) f = "%s %s/%s".formatted(i, n, d);
else f = "%s/%s".formatted(n, d);

Fractions

f := FloatToFraction(a);

Origin

from math import gcd

i, n = str(a).split('.')
d = 10 ** len(n)
i, n = map(int, (i, n))
factor = gcd(n, d) or 1
n //= factor
d //= factor
if not n:
    s = str(i)
elif not i:
    s = f'{n}/{d}'
else:
    s = f'{i} {n}/{d}'

from fractions import Fraction

f = Fraction(a)

from fractions import Fraction

def mixed_number(value) -> str:
    value = Fraction(str(value))
    signed = value < 0
    integer = 0
    n, d = value.as_integer_ratio()
    if signed:
        n = -n
    if n and (n > d):
        integer, n = divmod(n, d)
    if n == d:
        integer = n
        n = 0
    if not integer and n:
        s = f'{n}/{d}'
    elif not n:
        s = str(integer)
    else:
        s = f'{integer} {n}/{d}'
    if signed:
        s = f'-({s})'
    return s
F: str = mixed_number(A)

Preview