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histograms

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javi 2015-11-17 14:55:43 +01:00
parent f399acb8cc
commit b210ba8b22
2 changed files with 46 additions and 66 deletions
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31
lib/torque/leaflet/torque.js
View File

@ -212,25 +212,24 @@ L.TorqueLayer = L.CanvasLayer.extend({
}
},
getHistogramForVisibleRegion:function(varName,callback){
var center = this._map.getCenter()
var zoom = this._map.getZoom()
var xtile = parseInt(Math.floor( (center.lng + 180) / 360 * (1<<zoom) ));
var ytile = parseInt(Math.floor( (1 - Math.log(Math.tan(center.lat*Math.PI/180.0) + 1 / Math.cos(center.lat*Math.PI/180.0)) / Math.PI) / 2 * (1<<zoom) ));
var xx = xtile >> 2
var yy = ytile >> 2
var z = zoom - 2
this.provider.getHistogramForTiles(varName,[{x:xx,y:yy,z:z}],callback)
},
getHistogramForVisibleRegionBetter:function(varName,callback){
getHistogramForVisibleRegion: function(varName, callback){
var tiles= []
for(var key in this._tiles){
tiles.push(this._tiles[key].coord)
if (this._tiles[key]) {
tiles.push(this._tiles[key].coord)
}
}
this.provider.getHistogramForTiles(varName,tiles,callback)
var tilesFilter = this.provider._generateBoundsQuery(tiles);
this.provider.tablesForFilter(tilesFilter, function(tables) {
// select the table with less than 100k records
var table = tables.filter(function(f) {
return f.nrows < 50000;
})
table = table.length ? table[0].table_name: this.options.overview_tables[this.options.overview_tables.length - 1]
this.provider.getHistogramForTiles(varName, tiles, table, callback)
}.bind(this));
},
getHistogram:function(variable,callback,noBins){

81
lib/torque/provider/filterableJson.js
View File

@ -293,10 +293,14 @@ var Profiler = require('../profiler');
this.filters = filters
},
_generateFiltersSQL: function(escape_quotes) {
_generateFiltersSQL: function(escape_quotes, filter_columns) {
filter_columns = filter_columns || [];
escape_quotes = escape_quotes === undefined ? true: false;
var self = this;
return Object.keys(this._filters).map(function(filterName){
return Object.keys(this._filters).map(function(filterName) {
if (_.contains(filter_columns, filterName)) {
return ""
}
var filter = self._filters[filterName]
if (filter) {
if (filter.type == 'range') {
@ -608,41 +612,41 @@ var Profiler = require('../profiler');
this._setReady(true);
},
_generateBoundsQuery:function(tiles){
_generateBoundsQuery: function(tiles){
return tiles.map( function(tile){
return "(quadkey between (xyz2range("+tile.x+","+tile.y+","+tile.z+")).min and (xyz2range("+tile.x+","+tile.y+","+tile.z+")).max)"
}).join(" or ")
},
getHistogramForTiles: function(varName,tiles,callback){
getHistogramForTiles: function(varName, tiles, table, callback){
var sql = [
'with width as (',
'with source as (',
'select {varName} from {table} where ({bounds}) {filters}',
'),',
'width as (',
'select min({varName}) as min,',
'max({varName}) as max,',
'{bins} as buckets',
'from {table}',
'from source',
'),',
'_bw as ( select (max - min)/buckets as bw from width ),',
'histogram as (',
'select width_bucket({varName}, min, max, buckets) as bucket,',
'numrange(min({varName})::numeric, max({varName})::numeric, \'[]\') as range,',
'count(*) as freq',
'from {table}, width ',
'where {bounds}',
'{filters}',
//'where trip_time_in_secs between min and max',
'from source, width ',
'group by bucket',
'order by bucket',
')',
'select bucket*bw as start, (bucket+1)*bw as end, bucket as bin, lower(range) as min, upper(range) as max, freq from histogram, _bw;'
]
var filters = this._generateFiltersSQL() ? " and "+ this._generateFiltersSQL() : ""
var filters = this._generateFiltersSQL(false, [varName]) ? " and "+ this._generateFiltersSQL(false, [varName]) : ""
var query = format(sql.join('\n'), this.options, {
var query = format(sql.join('\n'), {
varName: varName,
table: this.options.table,
table: table,
filters: filters,
bounds: this._generateBoundsQuery(tiles),
bins: 20
@ -659,44 +663,21 @@ var Profiler = require('../profiler');
});
},
getHistogram: function(varName, callback) {
var sql = [
'with width as (',
'select min({column}) as min,',
'max({column}) as max,',
'20 as buckets',
'from {table}',
'),',
'_bw as ( select (max - min)/buckets as bw from width ),',
'histogram as (',
'select width_bucket({column}, min, max, buckets) as bucket,',
'numrange(min({column})::numeric, max({column})::numeric, \'[]\') as range,',
'count(*) as freq',
'from {table}, width ',
'where {filters}',
//'where trip_time_in_secs between min and max',
'group by bucket',
'order by bucket',
')',
'select bucket*bw as start, (bucket+1)*bw as end, bucket as bin, lower(range) as min, upper(range) as max, freq from histogram, _bw;'
]
var query = format(sql.join('\n'), this.options, {
column: varName,
table: this.options.table,
filters: this._generateFiltersSQL()
tablesForFilter: function(filter, callback) {
var filters = this._generateFiltersSQL()
if (filters) {
filters = "(" + filters + ") AND (" + filter + ")";
} else {
filters = filter;
}
// calcualte the table to fecth the histogram
// use the tile 0,0,0 using the quadkey range query
var sql = format("SELECT * FROM selectivity(x:=0, y:=0, z:=0, tables:=ARRAY[{overview_tables}], where_clause:='{filters}') order by nrows desc", {
overview_tables: this.options.overview_tables.map(function(t) { return "'" + t + "'"; }).join(','),
filters: filters
});
var self = this;
this.sql(query, function (data) {
if (data) {
var rows = JSON.parse(data.responseText).rows;
callback(rows);
} else {
callback(null);
}
this.sql(sql, function(data) {
callback(JSON.parse(data.responseText).rows);
});
}