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ReIm

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description

ReIm[z] gives {Re[z], Im[z]}, the real and imaginary parts of numeric z as a list; real-valued arguments give {z, 0}.

Examples (4)

Every input below was run against the current Mathilda build and its output recorded.

Applications (4)

In[1]:= ReIm[3 + 4 I]
Out[1]= {3, 4}

In[2]:= ReIm[(2 + I)^3]
Out[2]= {2, 11}

In[3]:= ReIm[(3 + 4 I)/(1 - 2 I)]
Out[3]= {-1, 2}

In[4]:= ReIm[N[E^(I Pi/4), 20]]
Out[4]= {0.707106781186547524409, 0.707106781186547524395}

Implementation notes

builtin_reim returns {Re[z], Im[z]} as a two-element List. It mirrors builtin_re/builtin_im: {f[z], 0} for real-valued head calls (Re/Im/Abs/Arg), {re, im} for a Complex[re, im] literal, {x, 0} for real numeric kinds (Integer/Real/Rational), and {re, im} when complex_decompose yields numeric parts. Returns NULL (unevaluated) for genuinely symbolic input.

Attributes: Listable, NumericFunction, Protected.

References

See also: Re, Im, Abs, Sign, Conjugate, Arg, Rational, Complex

Notes & additional examples

Notes

ReIm[z] is shorthand for {Re[z], Im[z]}; a real-valued argument gives {z, 0}.