Changed alist-to-pchk so it no longer requires zero padding of index …

…lists.

alist-to-pchk.c

@@ -44,6 +44,7 @@ int main
   int *rw, *cw;
   int i, j, k;
   int tot, trans;
+  int nxt;
 
   trans = 0;
 
@@ -98,42 +99,32 @@ int main
 
   H = mod2sparse_allocate(M,N);
 
+  do { if (fscanf(af,"%d",&nxt)!=1) nxt = -1; } while (nxt==0);
+
   tot = 0;
 
   for (i = 0; i<M; i++)
-  { for (k = 0; k<mxrw; k++)
-    { if (fscanf(af,"%d",&j)!=1 || j<0 || j>N
-       || k>=rw[i] && j!=0 || k<rw[i] && j==0)
+  { for (k = 0; k<rw[i]; k++)
+    { if (nxt<=0 || nxt>N || mod2sparse_find(H,i,nxt-1))
       { bad_alist_file();
       }
-      if (j==0) continue;
-      if (mod2sparse_find(H,i,j-1))
-      { bad_alist_file();
-      }
-      mod2sparse_insert(H,i,j-1);
+      mod2sparse_insert(H,i,nxt-1);
       tot += 1;
+      do { if (fscanf(af,"%d",&nxt)!=1) nxt = -1; } while (nxt==0);
     }
   }
 
   for (j = 0; j<N; j++)
-  { for (k = 0; k<mxcw; k++)
-    { if (fscanf(af,"%d",&i)!=1 || i<0 || i>M
-       || k>=cw[j] && i!=0 || k<cw[j] && i==0)
-      { bad_alist_file();
-      }
-      if (i==0) continue;
-      if (!mod2sparse_find(H,i-1,j))
+  { for (k = 0; k<cw[j]; k++)
+    { if (nxt<=0 || nxt>M || !mod2sparse_find(H,nxt-1,j))
       { bad_alist_file();
       }
       tot -= 1;
+      do { if (fscanf(af,"%d",&nxt)!=1) nxt = -1; } while (nxt==0);
     }
   }
 
-  if (tot!=0)
-  { bad_alist_file();
-  }
-
-  if (fscanf(af,"%d",&i)==1 || !feof(af))
+  if (tot!=0 || nxt!=-1 || !feof(af))
   { bad_alist_file();
   }
 

pchk.html

@@ -145,6 +145,13 @@ <H1> Creating a Parity Check Matrix </H1>
 matrix in <TT><I>alist-file</I></TT> is stored in the
 <TT><I>pchk-file</I></TT>.
 
+<P>Any zeros indexes in the alist file are ignored, so that alist files
+with zero padding (as required in the specification) are accepted,
+but files without this zero padding are also accepted.  Newlines
+are ignored by <TT>alist-to-pchk</TT>, so no error is reported if
+the set of indexes in a row or column description are not those
+on a single line.
+
 
 <P><A NAME="pchk-to-alist"><HR><B>pchk-to-alist</B>: Convert a parity
 check matrix to alist format.
@@ -167,7 +174,9 @@ <H1> Creating a Parity Check Matrix </H1>
 says that the list of indexes of 1s for each row or column should
 be padded with zeros to the maximum number of indexes.  By default,
 <TT>pchk-to-alist</TT> does this, but output of these 0s can be
-suppressed by specifying the <B>-z</B> option.
+suppressed by specifying the <B>-z</B> option.  (The <TT>alist-to-pchk</TT>
+program will accept alist files produced with or without the <B>-z</B>
+option.)
 
 
 <P><A NAME="print-pchk"><HR><B>print-pchk</B>: Print a parity check matrix.

release.html

@@ -31,6 +31,9 @@ <H2>Release to come.</H2>
      row and column indexes that pad up to the maximum number used.
 <LI> Documented the previously undocumented -t options for pchk-to-alist
      and alist-to-pchk.
+<LI> Changed alist-to-pchk so that it no longer requires zero indexes
+     that pad out to the maximum needed for a row or column (thanks
+     to Monica Kolb for suggesting this).
 <LI> Changed mod2word type in mod2dense.c to uint32_t, to avoid
      wasted space when long is 64 bits (thanks to Mathieu Cunche 
      and Vincent Roca for suggesting this).