a-floating-point-system

A floating-point system

A floating-point number can be represented as mantissa * radix ^ exponent (^ is raising radix to power exponent). In this kata we will be given a positive float aNumber and we want to decompose it into a positive integer mantissa composed of a given number of digits (called digitsNumber) and of an exponent.

Example:

aNumber = 0.06

If the number of digits asked for the mantissa is digitsNumber = 10 one can write

aNumber : 6000000000 * 10 ^ -11

the exponent in this example est -11.

Task

The function mantExp(aNumber, digitsNumber) will return aNumber in the form of a string: "mantissaPexponent" (concatenation of "mantissa", "P", "exponent").

Examples:

mantExp(0.06, 10) returns "6000000000P-11".
mantExp(72.0, 12)   returns "720000000000P-10"
mantExp(1.0, 5) returns "10000P-4"
mantExp(123456.0, 4) returns "1234P2"

Notes:

• In some languages aNumber could be given in the form of a string:

mantExp("0.06", 10) returns "6000000000P-11".

• 1 <= digitsNumber <= 15
• 0 < aNumber < 5.0 ^ 128