The GetRule( name ) command returns the procedure that performs the action of the rule name.

There is no procedure available for the rule 'digits'.

For more information on predefined rules in ScientificErrorAnalysis, see Predefined Rounding Rules.

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

$\mathrm{GetRule}\left(\mathrm{round}\right)$

$\mathbf{proc}\left(x\&comma;y\right)\mathbf{local}\mathrm{xp}\&comma;\mathrm{yp}\&comma;n\&comma;\mathrm{usen}\&semi;\mathbf{if}\mathbf{not}\mathrm{type}\left(\mathrm{procname}\&comma;\&apos;\mathrm{indexed}\&apos;\right)\mathbf{then}\mathbf{error}''`round`\; must\; be\; indexed''\mathbf{end\; if}\&semi;n≔\mathrm{op}\left(\mathrm{procname}\right)\&semi;\mathbf{if}\mathbf{not}\mathrm{type}\left(n\&comma;\&apos;\mathrm{posint}\&apos;\right)\mathbf{then}\mathbf{error}''invalid\; index\; to\; `round`''\mathbf{end\; if}\&semi;\mathrm{xp}\&comma;\mathrm{yp}≔\mathrm{evalf}\left(x\right)\&comma;\mathrm{evalf}\left(y\right)\&semi;\mathbf{if}\mathrm{xp}<>0\mathbf{then}\mathrm{usen}≔n\&plus;\mathrm{ilog10}\left(\mathrm{SFloatMantissa}\left(\mathrm{xp}\right)\right)-\mathrm{ilog10}\left(\mathrm{SFloatMantissa}\left(\mathrm{yp}\right)\right)\&plus;\mathrm{SFloatExponent}\left(\mathrm{xp}\right)-\mathrm{SFloatExponent}\left(\mathrm{yp}\right)\&semi;\mathbf{if}\mathrm{type}\left(\mathrm{usen}\&comma;\&apos;\mathrm{integer}\&apos;\right)\mathbf{then}\mathbf{if}\mathrm{usen}<1\mathbf{then}0.\&comma;\mathrm{evalf}\&lsqb;n\&rsqb;\left(\mathrm{yp}\right)\mathbf{else}\mathrm{evalf}\&lsqb;\mathrm{usen}\&rsqb;\left(\mathrm{xp}\right)\&comma;\mathrm{evalf}\&lsqb;n\&rsqb;\left(\mathrm{yp}\right)\mathbf{end\; if}\mathbf{else}\mathrm{evalf}\&lsqb;n\&rsqb;\left(\mathrm{xp}\right)\&comma;\mathrm{evalf}\&lsqb;n\&rsqb;\left(\mathrm{yp}\right)\mathbf{end\; if}\mathbf{else}0.\&comma;\mathrm{evalf}\&lsqb;n\&rsqb;\left(\mathrm{yp}\right)\mathbf{end\; if}\mathbf{end\; proc}$