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István Zachar
István Zachar
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There are multiple ways to convert an expression to machine precision, for example:

In[1]:= a = Sqrt[2]
Out[1]= Sqrt[2]

In[2]:= {1.a, 1`a, N@a, SetPrecision[a,MachinePrecision]}
Out[2]= {1.41421,1.41421,1.41421,1.41421}

In[3]:= Precision /@ %
Out[3]= {MachinePrecision,MachinePrecision,MachinePrecision,MachinePrecision}

My question is whether or not these methods are absolutely equivalent. Is isit just a matter of personal taste which one to use, or are there examples where they behave differently?

There are multiple ways to convert an expression to machine precision, for example:

In[1]:= a = Sqrt[2]
Out[1]= Sqrt[2]

In[2]:= {1.a, 1`a, N@a, SetPrecision[a,MachinePrecision]}
Out[2]= {1.41421,1.41421,1.41421,1.41421}

In[3]:= Precision /@ %
Out[3]= {MachinePrecision,MachinePrecision,MachinePrecision,MachinePrecision}

My question is whether or not these methods are absolutely equivalent. Is is just a matter of personal taste which one to use, or are there examples where they behave differently?

There are multiple ways to convert an expression to machine precision, for example:

In[1]:= a = Sqrt[2]
Out[1]= Sqrt[2]

In[2]:= {1.a, 1`a, N@a, SetPrecision[a,MachinePrecision]}
Out[2]= {1.41421,1.41421,1.41421,1.41421}

In[3]:= Precision /@ %
Out[3]= {MachinePrecision,MachinePrecision,MachinePrecision,MachinePrecision}

My question is whether or not these methods are absolutely equivalent. Is it just a matter of personal taste which one to use, or are there examples where they behave differently?

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Simon Woods
Simon Woods
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Converting to machine precision

There are multiple ways to convert an expression to machine precision, for example:

In[1]:= a = Sqrt[2]
Out[1]= Sqrt[2]

In[2]:= {1.a, 1`a, N@a, SetPrecision[a,MachinePrecision]}
Out[2]= {1.41421,1.41421,1.41421,1.41421}

In[3]:= Precision /@ %
Out[3]= {MachinePrecision,MachinePrecision,MachinePrecision,MachinePrecision}

My question is whether or not these methods are absolutely equivalent. Is is just a matter of personal taste which one to use, or are there examples where they behave differently?