ipld-eth-server/vendor/gopkg.in/karalabe/cookiejar.v2/ai/utility/inputset.go
Matt K 293dd2e848 Add vendor dir (#16) (#4)
* Add vendor dir so builds dont require dep

* Pin specific version go-eth version
2018-01-29 13:44:18 -06:00

122 lines
3.2 KiB
Go

// CookieJar - A contestant's algorithm toolbox
// Copyright (c) 2014 Peter Szilagyi. All rights reserved.
//
// CookieJar is dual licensed: use of this source code is governed by a BSD
// license that can be found in the LICENSE file. Alternatively, the CookieJar
// toolbox may be used in accordance with the terms and conditions contained
// in a signed written agreement between you and the author(s).
package utility
import (
"fmt"
"gopkg.in/karalabe/cookiejar.v2/collections/bag"
)
// Data-source based utility set, normalizing and transforming multiple input
// streams by an assigned curve.
type inputSetUtility struct {
curve Curve // Data transformation curve
min, max float64 // Normalization limits
nonZero bool // Flag whether absolute zero output is allowed
members map[int]*inputUtility // Members of this utility set
deps *bag.Bag // Derived utilities based on the current one
}
// Creates a new data source utility and associated a transformation curve.
func newInputSetUtility(curve Curve, nonZero bool) *inputSetUtility {
return &inputSetUtility{
curve: curve,
nonZero: nonZero,
members: make(map[int]*inputUtility),
deps: bag.New(),
}
}
// Sets the data limits used during normalization.
func (u *inputSetUtility) Limit(min, max float64) {
u.min, u.max = min, max
// Update any already initialized members
for _, util := range u.members {
util.Limit(min, max)
}
}
// Adds a new dependency to the utility hierarchy.
func (u *inputSetUtility) Dependency(util utility) {
// Store the dependency for yet unborn members
u.deps.Insert(util)
// Update all existing members
for id, member := range u.members {
switch v := util.(type) {
case *comboUtility:
member.Dependency(v)
case *comboSetUtility:
member.Dependency(v.Member(id))
default:
panic(fmt.Sprintf("Unknown dependency to inject: %+v", v))
}
}
}
// Retrieves a member of the utility set.
func (u *inputSetUtility) Member(id int) singleUtility {
if util, ok := u.members[id]; ok {
return util
} else {
u.spawn(id)
return u.members[id]
}
}
// Updates the utility of a member to a new data value.
func (u *inputSetUtility) Update(id int, input float64) {
// Create the member if not seen yet
if _, ok := u.members[id]; !ok {
u.spawn(id)
}
// Update the input of the member
u.members[id].Update(input)
}
// Resets a member utility, requiring a reevaluation.
func (u *inputSetUtility) Reset(id int) {
if util, ok := u.members[id]; ok {
util.Reset()
}
}
// Returns the utility value for member for the set data point.
func (u *inputSetUtility) Evaluate(id int) float64 {
// Create the member if not seen yet
if _, ok := u.members[id]; !ok {
u.spawn(id)
}
// Evaluate the member and return
return u.members[id].Evaluate()
}
// Creates a new member utility.
func (u *inputSetUtility) spawn(id int) {
// Create the base utility
util := newInputUtility(u.curve, u.nonZero)
util.Limit(u.min, u.max)
u.members[id] = util
// Inject any pending dependencies
u.deps.Do(func(dep interface{}) {
switch v := dep.(type) {
case *comboUtility:
util.Dependency(v)
case *comboSetUtility:
util.Dependency(v.Member(id))
default:
panic(fmt.Sprintf("Unknown dependency to inject: %+v", v))
}
})
}