This command simply changes the current frame to M.

The procedure returns the name of the previously active frame.

This command is part of the DifferentialGeometry package, and so can be used in the form ChangeFrame(...) only after executing the command with(DifferentialGeometry).  It can always be used in the long form DifferentialGeometry:-ChangeFrame.

$\mathrm{with}\left(\mathrm{DifferentialGeometry}\right)\:$

$\mathrm{DGsetup}\left(\left[x\,y\right]\,M\right)\:$$\mathrm{DGsetup}\left(\left[u\,v\right]\,N\right)\:$$\mathrm{DGsetup}\left(\left[x\,y\,z\right]\,P\right)\:$

$\mathrm{ChangeFrame}\left(M\right)$

$P$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(''CurrentFrame''\right)$

$M$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(''FrameBaseVectors''\right)$

$\left[\mathrm{D\_x}\,\mathrm{D\_y}\right]$

$\mathrm{ChangeFrame}\left(N\right)$

$M$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(''CurrentFrame''\right)$

$N$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(''FrameBaseVectors''\right)$

$\left[\mathrm{D\_u}\,\mathrm{D\_v}\right]$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_x}\,''ObjectFrame''\right),\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_y}\,''ObjectFrame''\right),\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_z}\,''ObjectFrame''\right)$

$M,M,P$

$\mathrm{ChangeFrame}\left(P\right)$

$N$

$\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_x}\,''ObjectFrame''\right),\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_y}\,''ObjectFrame''\right),\mathrm{Tools}:-\mathrm{DGinfo}\left(\mathrm{D\_z}\,''ObjectFrame''\right)$

$P,P,P$