PST: Fast Float Serialization

Given float numbers of precision 3 (rounded to decimal places), e.g. 0.123. Following method can de/serialize float numbers safely across platforms of different endianness.

// Serialization  
float number[100];  
std::ofstream fout(“output”);  
for(int i=0;i<100;++i)  
	fout<< (number*1000) <<endl;

// De-serialization  
int value;  
float result[100];  
std::ifstream fin(“input”);  
for(int i=0;i<100;++i){  
	fin>>value;  
	result[i] = value/1000.0;  
}

By translating float number to a discrete form, the cost of de/serialization (text to double) is reduced since it becomes a text to integer conversion.

• Original posted in my Tumblr

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Update: Another technique

union {
  int ival;
  float fval;
} number;
number.fval = 0.1234; 
fout << number.ival;
fout >> number.ival;
// use number.fval

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