From a15e3e1d43fd6acca437e0396f8db4e3d72fb10c Mon Sep 17 00:00:00 2001
From: Adrian Mariano <avm4@cornell.edu>
Date: Sat, 10 Dec 2022 09:49:04 -0500
Subject: [PATCH] screws fix, arc_copies doc fix, sortidx bugfix

---
 comparisons.scad            | 1 -
 distributors.scad           | 2 +-
 screws.scad                 | 5 +++--
 tests/test_comparisons.scad | 4 ++++
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/comparisons.scad b/comparisons.scad
index 15ea570..6dc8379 100644
--- a/comparisons.scad
+++ b/comparisons.scad
@@ -728,7 +728,6 @@ function sort(list, idx=undef) =
 //   idxs3 = sortidx(lst, idx=[1,3]); // Returns: [3,0,2,1]
 function sortidx(list, idx=undef) = 
     assert(is_list(list)||is_string(list), "Invalid list." )
-    !is_list(list) || len(list)<=1 ? list :
     is_homogeneous(list,1)
     ?   let( 
             size = list_shape(list[0]),
diff --git a/distributors.scad b/distributors.scad
index 36adb19..cdbe179 100644
--- a/distributors.scad
+++ b/distributors.scad
@@ -775,7 +775,7 @@ module zrot_copies(rots=[], cp=[0,0,0], n, sa=0, r, d, subrot=true)
 //   d = diameter of circle. (Default: 2)
 //   dx = diameter of ellipse on X axis. Used instead of d.
 //   dy = diameter of ellipse on Y axis. Used instead of d.
-//   rot = whether to rotate the copied children.  (Default: false)
+//   rot = whether to rotate the copied children.  (Default: true)
 //   sa = starting angle. (Default: 0.0)
 //   ea = ending angle. Will distribute copies CCW from sa to ea. (Default: 360.0)
 //
diff --git a/screws.scad b/screws.scad
index adb4d2c..97ebfab 100644
--- a/screws.scad
+++ b/screws.scad
@@ -925,11 +925,12 @@ module screw_hole(spec, head, thread, oversize, hole_oversize, head_oversize,
                    parse_int(substr(tolerance,1))
              : assert(false,str("Unknown tolerance ",tolerance, " for clearance hole"));
      tol_table = struct_val(screwspec,"system")=="UTS" ? UTS_clearance[tol_ind] : ISO_clearance[tol_ind];
+     tol_gap = lookup(_nominal_diam(screwspec), tol_table);
      // If we got here, hole_oversize is undefined and oversize is undefined
      hole_oversize = downcase(tolerance)=="tap" ? -pitch
                    : downcase(tolerance)=="self tap" ? -pitch*lookup(pitch,[[1,0.72],[1.5,.6]])
-                   : lookup(_nominal_diam(screwspec), tol_table);
-     head_oversize = first_defined([head_oversize,hole_oversize]);
+                   : tol_gap;
+     head_oversize = default(head_oversize, tol_gap);
      default_tag("remove")     
        screw(spec,head=head,thread=0,shaft_undersize=-hole_oversize, head_undersize=-head_oversize, 
              length=length,l=l,thread_len=thread_len, _counterbore=counterbore,
diff --git a/tests/test_comparisons.scad b/tests/test_comparisons.scad
index 56b2f96..31ec78f 100644
--- a/tests/test_comparisons.scad
+++ b/tests/test_comparisons.scad
@@ -16,6 +16,10 @@ test_sort();
 
 
 module test_sortidx() {
+    assert(sortidx([3]) == [0]);
+    assert(sortidx([]) == []);
+    assert(sortidx([[5,6,7]])==[0]);
+    assert(sortidx(["abc"]) == [0]);
     lst1 = ["da","bax","eaw","cav"];
     assert(sortidx(lst1) == [1,3,0,2]);
     lst5 = [3,5,1,7];