--- ray/doc/man/man1/rcomb.1	2024/01/17 21:50:15	1.5
+++ ray/doc/man/man1/rcomb.1	2024/05/07 17:15:31	1.7
@@ -1,4 +1,4 @@
-.\" RCSid "$Id: rcomb.1,v 1.5 2024/01/17 21:50:15 greg Exp $"
+.\" RCSid "$Id: rcomb.1,v 1.7 2024/05/07 17:15:31 greg Exp $"
 .TH RCOMB 12/5/2023 RADIANCE
 .SH NAME
 rcomb - combine and convert matrices a row at a time
@@ -53,7 +53,7 @@ or
 .I \-s
 options follow the last input matrix, output results will be transformed
 and/or scaled accordingly.
-These operations are discussed in greater detail further on.
+These operations are discussed in greater detail below.
 A single concatenation matrix may be applied after element operations
 using the
 .I \-m
@@ -71,7 +71,7 @@ FORMAT={ascii|float|double|32-bit_rle_rgbe|32-bit_rle_
 .fi
 .sp
 The number of components indicates that each matrix element is actually
-composed of multiple elements, most commonly an RGB triple.
+composed of multiple channels, most commonly an RGB triple.
 This is essentially dividing the matrix into planes, where each component
 participates in a separate calculation.
 If an appropriate header is not present, it may be added with a call to
@@ -188,8 +188,8 @@ If the
 or
 .I \-f
 options are used to define a "co" variable or "co(p)" function,
-this will be evaluated at each output
-component for the current element.
+which will be evaluated for each output
+component from the current element.
 The "co" variable defines identical operations for all components,
 whereas "co(p)" may specify different operations for each component.
 The element position is defined
@@ -207,7 +207,7 @@ and the number of components is defined by the "ncomp"
 If given as "ci(i)", the function returns the current component
 being evaluated by
 .I rcomb.
-A different component may be referenced using th second argument.
+A different component may be referenced using the second argument.
 For example, "ci(1,2)" accesses
 the second component from the first input.
 If the input is a picture, the the constants "R", "G", and "B"
@@ -222,7 +222,8 @@ For convenience and compatibility with
 the functions "ri(i)", "gi(i)", and "bi(i)" are predefined as
 "ci(i,R)", "ci(i,G)", and "ci(i,B)", respectively.
 Accordingly, the "ro", "go", and "bo" 
-variables may be used in place of "co(R)", "co(G)", and "co(B)".
+variables may be used in place of "co(R)", "co(G)", and "co(B)",
+but all three must be defined for this substitution to take place.
 Finally, the total number of input files is set in the constant "nfiles".
 .PP
 Results are sent to the standard output.
@@ -280,7 +281,7 @@ and
 .I pcomb,
 whose capabilities somewhat overlap.
 The former loads each matrix into memory before operations,
-and element components take 8 bytes apiece, adding up quickly.
+and element components are stored as double-precision.
 Very large matrices therefore present a problem with that tool.
 Furthermore, 
 .I rmtxop
@@ -313,18 +314,18 @@ Generally speaking,
 .I rcomb
 should be preferred over
 .I rmtxop
-for any operations in can handle, which is everything except
+for any operations it can handle, which is everything except
 multiple matrix concatenations and transpose
-operations, which are handled more efficiently by
-.I rcollate(1)
-in any case.
+operations.
+The latter may be handled more efficiently by
+.I rcollate(1).
 That said, there is no significant difference for
-simple operations on smallish matrices, and note that only
+simple operations on small matrices, and only
 .I rmtxop
 and
 .I dctimestep(1)
-currently accept XML files as inputs.
-Also, the resizing function of
+accept XML files as inputs.
+Also note that the resizing function of
 .I pcomb
 is not supported in
 .I rcomb,