@spiceErrorCheck<EOL>def sxform(instring, tostring, et):
instring = stypes.stringToCharP(instring)<EOL>tostring = stypes.stringToCharP(tostring)<EOL>xform = stypes.emptyDoubleMatrix(x=<NUM_LIT:6>, y=<NUM_LIT:6>)<EOL>if hasattr(et, "<STR_LIT>"):<EOL><INDENT>xforms = []<EOL>for t in et:<EOL><INDENT>libspice.sxform_c(instring, tostring, ctypes.c_double(t), xform)<EOL>checkForSpiceError(None)<EOL>xforms.append(stypes.cMatrixToNumpy(xform))<EOL><DEDENT>return xforms<EOL><DEDENT>else:<EOL><INDENT>et = ctypes.c_double(et)<EOL>libspice.sxform_c(instring, tostring, et, xform)<EOL>return stypes.cMatrixToNumpy(xform)<EOL><DEDENT>
Return the state transformation matrix from one frame to
another at a specified epoch.

http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/sxform_c.html


:param instring: Name of the frame to transform from.
:type instring: str
:param tostring: Name of the frame to transform to.
:type tostring: str
:param et: Epoch of the state transformation matrix.
:type et: Union[float,Iterable[float]]
:return: A state transformation matrix.
:rtype: 6x6-Element Array of floats