diff options
author | Hans-Christoph Steiner <hans@eds.org> | 2012-03-30 20:42:12 -0400 |
---|---|---|
committer | Hans-Christoph Steiner <hans@eds.org> | 2012-03-30 20:42:12 -0400 |
commit | 7bb481fda9ecb134804b49c2ce77ca28f7eea583 (patch) | |
tree | 31b520b9914d3e2453968abe375f2c102772c3dc /ext/rtree/rtree_util.tcl |
Imported Upstream version 2.0.3
Diffstat (limited to 'ext/rtree/rtree_util.tcl')
-rw-r--r-- | ext/rtree/rtree_util.tcl | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/ext/rtree/rtree_util.tcl b/ext/rtree/rtree_util.tcl new file mode 100644 index 0000000..50a1b58 --- /dev/null +++ b/ext/rtree/rtree_util.tcl @@ -0,0 +1,192 @@ +# 2008 Feb 19 +# +# The author disclaims copyright to this source code. In place of +# a legal notice, here is a blessing: +# +# May you do good and not evil. +# May you find forgiveness for yourself and forgive others. +# May you share freely, never taking more than you give. +# +#*********************************************************************** +# +# This file contains Tcl code that may be useful for testing or +# analyzing r-tree structures created with this module. It is +# used by both test procedures and the r-tree viewer application. +# + + +#-------------------------------------------------------------------------- +# PUBLIC API: +# +# rtree_depth +# rtree_ndim +# rtree_node +# rtree_mincells +# rtree_check +# rtree_dump +# rtree_treedump +# + +proc rtree_depth {db zTab} { + $db one "SELECT rtreedepth(data) FROM ${zTab}_node WHERE nodeno=1" +} + +proc rtree_nodedepth {db zTab iNode} { + set iDepth [rtree_depth $db $zTab] + + set ii $iNode + while {$ii != 1} { + set sql "SELECT parentnode FROM ${zTab}_parent WHERE nodeno = $ii" + set ii [db one $sql] + incr iDepth -1 + } + + return $iDepth +} + +# Return the number of dimensions of the rtree. +# +proc rtree_ndim {db zTab} { + set nDim [expr {(([llength [$db eval "pragma table_info($zTab)"]]/6)-1)/2}] +} + +# Return the contents of rtree node $iNode. +# +proc rtree_node {db zTab iNode {iPrec 6}} { + set nDim [rtree_ndim $db $zTab] + set sql " + SELECT rtreenode($nDim, data) FROM ${zTab}_node WHERE nodeno = $iNode + " + set node [db one $sql] + + set nCell [llength $node] + set nCoord [expr $nDim*2] + for {set ii 0} {$ii < $nCell} {incr ii} { + for {set jj 1} {$jj <= $nCoord} {incr jj} { + set newval [format "%.${iPrec}f" [lindex $node $ii $jj]] + lset node $ii $jj $newval + } + } + set node +} + +proc rtree_mincells {db zTab} { + set n [$db one "select length(data) FROM ${zTab}_node LIMIT 1"] + set nMax [expr {int(($n-4)/(8+[rtree_ndim $db $zTab]*2*4))}] + return [expr {int($nMax/3)}] +} + +# An integrity check for the rtree $zTab accessible via database +# connection $db. +# +proc rtree_check {db zTab} { + array unset ::checked + + # Check each r-tree node. + set rc [catch { + rtree_node_check $db $zTab 1 [rtree_depth $db $zTab] + } msg] + if {$rc && $msg ne ""} { error $msg } + + # Check that the _rowid and _parent tables have the right + # number of entries. + set nNode [$db one "SELECT count(*) FROM ${zTab}_node"] + set nRow [$db one "SELECT count(*) FROM ${zTab}"] + set nRowid [$db one "SELECT count(*) FROM ${zTab}_rowid"] + set nParent [$db one "SELECT count(*) FROM ${zTab}_parent"] + + if {$nNode != ($nParent+1)} { + error "Wrong number of entries in ${zTab}_parent" + } + if {$nRow != $nRowid} { + error "Wrong number of entries in ${zTab}_rowid" + } + + return $rc +} + +proc rtree_node_check {db zTab iNode iDepth} { + if {[info exists ::checked($iNode)]} { error "Second ref to $iNode" } + set ::checked($iNode) 1 + + set node [rtree_node $db $zTab $iNode] + if {$iNode!=1 && [llength $node]==0} { error "No such node: $iNode" } + + if {$iNode != 1 && [llength $node]<[rtree_mincells $db $zTab]} { + puts "Node $iNode: Has only [llength $node] cells" + error "" + } + if {$iNode == 1 && [llength $node]==1 && [rtree_depth $db $zTab]>0} { + set depth [rtree_depth $db $zTab] + puts "Node $iNode: Has only 1 child (tree depth is $depth)" + error "" + } + + set nDim [expr {([llength [lindex $node 0]]-1)/2}] + + if {$iDepth > 0} { + set d [expr $iDepth-1] + foreach cell $node { + set shouldbe [rtree_node_check $db $zTab [lindex $cell 0] $d] + if {$cell ne $shouldbe} { + puts "Node $iNode: Cell is: {$cell}, should be {$shouldbe}" + error "" + } + } + } + + set mapping_table "${zTab}_parent" + set mapping_sql "SELECT parentnode FROM $mapping_table WHERE rowid = \$rowid" + if {$iDepth==0} { + set mapping_table "${zTab}_rowid" + set mapping_sql "SELECT nodeno FROM $mapping_table WHERE rowid = \$rowid" + } + foreach cell $node { + set rowid [lindex $cell 0] + set mapping [db one $mapping_sql] + if {$mapping != $iNode} { + puts "Node $iNode: $mapping_table entry for cell $rowid is $mapping" + error "" + } + } + + set ret [list $iNode] + for {set ii 1} {$ii <= $nDim*2} {incr ii} { + set f [lindex $node 0 $ii] + foreach cell $node { + set f2 [lindex $cell $ii] + if {($ii%2)==1 && $f2<$f} {set f $f2} + if {($ii%2)==0 && $f2>$f} {set f $f2} + } + lappend ret $f + } + return $ret +} + +proc rtree_dump {db zTab} { + set zRet "" + set nDim [expr {(([llength [$db eval "pragma table_info($zTab)"]]/6)-1)/2}] + set sql "SELECT nodeno, rtreenode($nDim, data) AS node FROM ${zTab}_node" + $db eval $sql { + append zRet [format "% -10s %s\n" $nodeno $node] + } + set zRet +} + +proc rtree_nodetreedump {db zTab zIndent iDepth iNode} { + set ret "" + set node [rtree_node $db $zTab $iNode 1] + append ret [format "%-3d %s%s\n" $iNode $zIndent $node] + if {$iDepth>0} { + foreach cell $node { + set i [lindex $cell 0] + append ret [rtree_nodetreedump $db $zTab "$zIndent " [expr $iDepth-1] $i] + } + } + set ret +} + +proc rtree_treedump {db zTab} { + set d [rtree_depth $db $zTab] + rtree_nodetreedump $db $zTab "" $d 1 +} |