README.md: improve "Data File" section, add more benchmarks

2 files changed, 14 insertions, 11 deletions

diff --git a/README.md b/README.md
index 4554d22..ea107cd 100644
--- a/README.md
+++ b/README.md
@@ -55,17 +55,18 @@ Data File Format
 Reads and writes newline-delimited plain text files in the following
 format:
 
-* Lines are delimited by newlines
-* Each line is a record.
-* Record fields are delimited by whitespace.
-* The first row specifies the *shape* of the remaining rows as two
-  unsigned integers.  The first unsigned integer -- `num_floats` --
-  indicates the number of floating point columns per row, and the second
-  unsigned integer -- `num_ints` -- indicates the number of signed
-  integer values per row.
-* The remaining lines contain data rows.  Each row consists of
-  `num_floats` floating point numbers, followed by `num_ints` signed
-  integer values.
+* Each line is a row.
+* Each row consists of one or more columns, delimited by a space.
+* Columns are floating point or integer values.
+* The first row is called the header row.
+* The header row contains two unsigned integer columns which indicate
+  the layout of the remaining rows.
+* The first header row column indicates the number of floating
+  point columns per row (`num_floats`).
+* The second header row column indicates the number of integer
+  columns per row (`num_ints`).
+* The remaining rows contain `num_floats` floating point
+  columns, followed by `num_ints` signed integer columns.
 
 Example data file:
 
diff --git a/tests/bm.csv b/tests/bm.csv
index d6e2a19..c44e31a 100644
--- a/tests/bm.csv
+++ b/tests/bm.csv
@@ -2,4 +2,6 @@ file,real_time
 c4-1e5-0.dat,0m30.959s
 c4-1e5-0.dat,0m29.414s
 c4-1e5-0.dat,0m28.033s
+c4-1e5-0.dat,0m19.917s
+c4-1e5-0.dat,0m21.160s
 c9-1e6-0.dat,6m19.640s