X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=spv-file-format.texi;h=f9d698706e50acf0ba48e577f2f1647a2737a118;hb=8af10bb39253b97589c5f4b455b708c8fb9e233b;hp=c58723379517a7ddfd275184a96020313f147703;hpb=86009a9088ecdfddfacd7974f30b88cb89937d55;p=pspp

diff --git a/spv-file-format.texi b/spv-file-format.texi
index c587233795..f9d698706e 100644
--- a/spv-file-format.texi
+++ b/spv-file-format.texi
@@ -411,8 +411,12 @@ In every example in the corpus, @code{x2} is 18 and the bytes that
 follow it are @code{00 00 00 01 00 00 00 00 00 00 00 00 00 02 00 00 00
 00}.  The meaning of these bytes is unknown.
 
-Observed values of @code{x3} vary from 16 to 150.  The bytes that
-follow it vary somewhat.
+In every example in the corpus for version 1, @code{x3} is 16 and the
+bytes that follow it are @code{00 00 00 01 00 00 00 01 00 00 00 00 01
+01 01 01}.  In version 3, observed @code{x3} varies from 117 to 150 and
+the bytes that follow it vary somewhat and often include a readable
+text string, e.g. ``Default'' or ``Academic'', which appears to be the
+name of a ``TableLook''.
 
 Observed values of @code{x4} vary from 0 to 17.  Out of 7060 examples
 in the corpus, it is nonzero only 36 times.
@@ -554,3 +558,77 @@ are terminal categories that directly represent data values for a
 variable (e.g. in a frequency table or crosstabulation, a group of
 values in a variable being tabulated) and i0 otherwise, but this might
 be naive.
+
+@example
+data := int[layers] int[rows] int[columns] int*[n-dimensions]
+        int[n-data] datum*[n-data]
+@end example
+
+The values of @code{layers}, @code{rows}, and @code{columns} each
+specifies the number of dimensions represented in layers or rows or
+columns, respectively, and their values sum to the number of
+dimensions.
+
+The @code{n-dimensions} integers are a permutation of the 0-based
+dimension numbers.  The first @code{layers} of them specify each of
+the dimensions represented by layers, the next @code{rows} of them
+specify the dimensions represented by rows, and the final
+@code{columns} of them specify the dimensions represented by columns.
+When there is more than one dimension of a given kind, the inner
+dimensions are given first.
+
+@example
+datum := int64[index] 00? value      /* @r{version 1} */
+datum := int64[index] value          /* @r{version 3} */
+@end example
+
+The format of a datum varies slightly from version 1 to version 3: in
+version 1 it allows for an extra optional 00 byte.
+
+A datum consists of an index and a value.  Suppose there are @math{d}
+dimensions and dimension @math{i} for @math{0 \le i < d} has
+@math{n_i} categories.  Consider the datum at coordinates @math{x_i}
+for @math{0 \le i < d}; note that @math{0 \le x_i < n_i}.  Then the
+index is calculated by the following algorithm:
+
+@display
+let index = 0
+for each @math{i} from 0 to @math{d - 1}:
+    index = @math{n_i \times} index + @math{x_i}
+@end display
+
+For example, suppose there are 3 dimensions with 3, 4, and 5
+categories, respectively.  The datum at coordinates (1, 2, 3) has
+index @math{5 \times (4 \times (3 \times 0 + 1) + 2) + 3 = 33}.
+
+@example
+value := 00? 00? 00? 00? raw-value
+raw-value := 01 opt-value int32[format] double
+           | 02 opt-value int32[format] double string[varname] string[vallab]
+             (01 | 02 | 03)
+           | 03 string[local] opt-value string[id] string[c] (00 | 01)
+           | 04 opt-value int32[format] string[vallab] string[varname]
+             (01 | 02 | 03) string[vallab]
+           | 05 opt-value string[varname] string[varlabel] (01 | 02 | 03)
+           | opt-value string[format] int32[n-substs] substitution*[n-substs]
+substitution := i0 value
+              | int32[x] value*[x + 1]      /* @r{x > 0} */
+opt-value := 31 i0 (i0 | i1 string) opt-value-i0-v1        /* @r{version 1} */
+           | 31 i0 (i0 | i1 string) opt-value-i0-v3        /* @r{version 3} */
+           | 31 i1 int32[footnote-number] nested-string
+           | 31 i2 (00 | 02) 00 (i1 | i2 | i3) nested-string
+           | 31 i3 00 00 01 00 i2 nested-string
+           | 58
+opt-value-i0-v1 := 00 (i1 | i2) 00 00 int32 00 00
+opt-value-i0-v3 := count(counted-string
+                         (58
+                          | 31 01? 00? 00? 00? 01
+                            string[fgcolor] string[bgcolor] string[typeface]
+                            byte)
+                         (58
+                          | 31 i0 i0 i0 i0 01 00 (01 | 02 | 08)
+                            00 08 00 0a 00))
+
+nested-string := 00 00 count(counted-string 58 58)
+counted-string := count((i0 (58 | 31 string))?)
+@end example