[Maxima-commits] [git] Maxima CAS branch master updated. branch-5_48-base-182-g9ab39fcc3

[peterpall <pet...@us...>]

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "Maxima CAS".

The branch, master has been updated
       via  9ab39fcc3b33194ee7e818e65877337cd8c4a9f4 (commit)
      from  1d2475070c8162d444ebba633bcf90db07023a70 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
commit 9ab39fcc3b33194ee7e818e65877337cd8c4a9f4
Author: Gunter Königsmann <gu...@pe...>
Date:   Thu Sep 11 08:51:01 2025 +0200

    wrstcse: Added a new command that creates taylor series of tolerance dependencies
    
    Sometimes in engineering the trick is to simplify stuff by linearizing it.

diff --git a/share/contrib/wrstcse.mac b/share/contrib/wrstcse.mac
index dc79cc930..b95edae5c 100644
--- a/share/contrib/wrstcse.mac
+++ b/share/contrib/wrstcse.mac
@@ -366,6 +366,53 @@ wc_ewc_simplify(x):=block(
     return(x)
 );
 
+/* Sometimes the secret of engineering is simplifying something, for example by
+approximating it by a taylor series. This is what this function does do */
+wc_toltaylor(x,[maxorder]):=block(
+    [
+        /* The derivate of x to the tol[n] we currently look at */
+        wc_diffofwctol,
+        /* wc_diffofwctol for the current tol being 0 */
+        wc_diffofwctollimit,
+        retval:wc_typicalvalues(x)
+    ],
+    /* Determine the order of the taylor series we want to generate */
+    if maxorder = [] then maxorder:[1],
+    if length(maxorder) > 1 then error("wc_toltaylor: more than 2 arguments!"),
+    maxorder:maxorder[1],
+    if not numberp(maxorder) then error("wc_toltaylor: The 2nd argument must be a number!"),
+    if maxorder<0 then error("wc_toltaylor: The 2nd argument must not be negative!"),
+
+    /* Perform the taylor series for all tolerances */
+    for wc_tol in %wc_tols(x) do
+        for wc_difforder:1 thru maxorder do
+        (
+            /* Let's see if we can get the derivate we need the naive way */
+            wc_diffofwctol:%wc_typicalvalues(diff(x,wc_tol,wc_difforder),wc_tol),
+            wc_diffofwctollimit:limit(wc_diffofwctol,wc_tol,0),
+
+            /* If the derivate is 'ind we have two derivates at tol[n]=0 */
+            if wc_diffofwctollimit='ind then block([wc_poslimit,wc_neglimit],
+               /* We have two derivates. As we are performing a worst case
+                  calculation we make a worst-case assumption and use the bigger
+                  one ignoring its sign */
+               wc_poslimit:limit(wc_diffofwctol,wc_tol,0,'plus),
+               wc_neglimit:limit(wc_diffofwctol,wc_tol,0,'minus),
+               wc_diffofwctollimit:max(abs(wc_poslimit),abs(wc_neglimit)),
+               /* If we can determine which of the limits is bigger we can
+                  do without the abs() */
+               if abs(wc_poslimit) > abs(wc_neglimit) then
+                  wc_diffofwctollimit:wc_poslimit,
+               if abs(wc_poslimit) < abs(wc_neglimit) then
+                  wc_diffofwctollimit:wc_neglimit
+           ),
+           /* Add the taylor term we just learned about to the result */
+           retval:retval+wc_tol^wc_difforder/wc_difforder*wc_typicalvalues(wc_diffofwctollimit)
+        ),
+   return(retval)
+);
+
+
 wc_sensitivities(expr):=block([tols:[],wc_tol,wc_typ:wc_typicalvalues(expr),wc_result:[]],
     /* Compile a list of tol[n] */
     for i in listofvars(expr) do

-----------------------------------------------------------------------

Summary of changes:
 share/contrib/wrstcse.mac | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)


hooks/post-receive
-- 
Maxima CAS