Ruby BigDecimal log()函数

BigDecimal#log() : log()是BigDecimal类的一个方法，用于返回小数的自然对数，精度为指定位数的数值。

语法。BigDecimal.log()

参数。BigDecimal的数值

返回：小数的自然对数，精度为指定位数，数值。

例子 #1 :

# Ruby code for BigDecimal.log() method
  
# loading library
require 'bigdecimal'
  
# declaring bigdecimal
a = BigDecimal("10")
  
# declaring bigdecimal
b = BigDecimal("1000") *2
  
# declaring bigdecimal
c = BigDecimal("11.43")
  
# log() method
puts "BigDecimal a log method : #{Math.log(a)}\n\n"
  
puts "BigDecimal b log method : #{Math.log(b)}\n\n"
  
puts "BigDecimal a log method : #{Math.log(c)}\n\n"

输出:

BigDecimal a log method : 2.302585092994046

BigDecimal b log method : 7.600902459542082

BigDecimal a log method : 2.4362414778067194

例子 #2 :

# Ruby code for BigDecimal.log() method
  
# loading library
require 'bigdecimal'
  
# declaring bigdecimal
a = BigDecimal('12')*12
  
# declaring bigdecimal
b = BigDecimal('10')+(22 ** 7.1) ** 10
  
# declaring bigdecimal
c = -BigDecimal('-3')
  
# log() method
puts "BigDecimal a log method : #{Math.log(a)}\n\n"
  
puts "BigDecimal b log method : #{Math.log(b)}\n\n"
  
puts "BigDecimal a log method : #{Math.log(c)}\n\n"

输出:

BigDecimal a log method : 4.969813299576001

BigDecimal b log method : 219.46401418844042

BigDecimal a log method : 1.0986122886681098