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Transform a floating point number into a rational : exact
float2rational

float2rational or exact takes as argument a floating point number d and returns a rational number q approaching d such that abs(d-q)<epsilon. epsilon is defined in the cas configuration (Cfg menu) or with the cas_setup command.
Input :
float2rational(0.3670520231)
Output when epsilon=1e-10:
127/346
Input :
evalf(363/28)
Output :
12.9642857143
Input :
float2rational(12.9642857143)
Output :
363/28
If two representations are mixed, for example :
1/2+0.7
the rational is converted to a float, output :
1.2
Input :
1/2+float2rational(0.7)
Output :
6/5



giac documentation written by Renée De Graeve and Bernard Parisse