math - C++ Exp vs. Log: Which is faster? -


I have a C ++ application in which I need to compare two values ​​and make as many decisions as possible. The only complication is that a number is represented in the log-space, not the other. For example: 

  double log_num_1 = log (1.23); Double number_2 = 1.24;   
 If I want to compare  num_1  and  num_2 , then let me use the  log  Or  exp () , and I am thinking that it is easy to compare with one another (i.e. runs in less time in normal time). You can assume that I am using the standard  cmath  library. 
 
 In other words, the following meanings are equivalent, which is faster: 
 
  if (exp (log_num_1)> num_2)) cout & lt; & Lt; "Num_1 is big";  
 
 or 
 
  if (log_num_1 & gt; log (num_2)) cout & lt; & Lt; "Num_1 is big"; APIAL algorithm, complexity is the same, the only difference should be ( 
 
 
 
 Hopefully negligible ) Continued due to this, I have  exp (a) & gt; B , because it does not break on invalid input.

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