TfLogisticGrowth
サマリー
Defines a Logistic Growth transformation function which is determined from the minimum, maximum, and y intercept percent shape–controlling parameters as well as the lower and upper threshold that identify the range within which to apply the function.
Learn more about how the parameters affect this transformation function
ディスカッション
The tool that uses the TfLogisticGrowth object is Rescale by Function.
The function values range from 0 to 100, which are then transformed to the evaluation scale.
If the minimum parameter is set greater than the lowerThreshold, or the maximum parameter is set less than the upperThreshold, the function curve will increase at a faster rate. If the minimum parameter is set less than the lowerThreshold, or the maximum parameter is set greater than the upperThreshold, the function curve will increase at a slower rate.
構文
TfLogisticGrowth({minimum}, {maximum}, {yInterceptPercent}, {lowerThreshold}, {valueBelowThreshold}, {upperThreshold}, {valueAboveThreshold})
| 名前 | 説明 | データ タイプ |
|---|---|---|
|
minimum (オプション) |
The starting point for the The minimum must be less than the maximum. The default value is None. |
Double |
|
maximum (オプション) |
The ending point for the The minimum must be less than the maximum. The default value is None. |
Double |
|
yInterceptPercent (オプション) |
Determines the value range in the increasing portion of the logistic growth curve. The smaller the The The default value is 1.0. |
Double |
|
lowerThreshold (オプション) |
Defines the starting value at which to begin applying the specified transformation function. The input value corresponding to the The The default value is None. |
Double |
|
valueBelowThreshold (オプション) |
A value to assign output cell locations with input values below the The value for The default value is None. |
Variant |
|
upperThreshold (オプション) |
Defines the ending value at which to stop applying the specified transformation function. The input value corresponding to the The The default value is None. |
Double |
|
valueAboveThreshold (オプション) |
A value to assign output cell locations with input values above the The value for The default value is None. |
Variant |
プロパティ
| 名前 | 説明 | データ タイプ |
|---|---|---|
|
minimum (読み取り/書き込み) |
The value of the |
Double |
|
maximum (読み取り/書き込み) |
The value of the |
Double |
|
yInterceptPercent (読み取り/書き込み) |
The value of the |
Double |
|
lowerThreshold (読み取り/書き込み) |
The value of the |
Double |
|
valueBelowThreshold (読み取り/書き込み) |
The value that will be assigned to the output cells whose input values are below the |
Variant |
|
upperThreshold (読み取り/書き込み) |
The value of the |
Double |
|
valueAboveThreshold (読み取り/書き込み) |
The value that will be assigned to the output cells whose input values are above the |
Variant |
コードのサンプル
Demonstrates how to create a TfLogisticGrowth class and use it in the RescaleByFunction tool within the Python window.
import arcpy
from arcpy.sa import *
from arcpy import env
env.workspace = "c:/sapyexamples/data"
outRescale = RescaleByFunction("biomass", TfLogisticGrowth(30, 412000, 15, "#", "#", "#", "#"), 1, 10)
outRescale.save("c:/sapyexamples/rescaletflg1")
Demonstrates how to transform the input data with the RescaleByFunction tool using the TfLogisticGrowth class.
# Name: TfLogisticGrowth_Ex_02.py
# Description: Rescales input raster data using a LogisticGrowth function and
# transforms the function values onto a specified evaluation scale.
# Requirements: Spatial Analyst extension
# Import system modules
import arcpy
from arcpy import env
from arcpy.sa import *
# Set environment settings
env.workspace = "C:/sapyexamples/data"
# Set local variables
inRaster = "biomass"
# Create the TfLogisticGrowth object
minimum = 30
maximum = 412000
yintercept = 15
lowerthresh = "#"
valbelowthresh = "#"
upperthresh = "#"
valabovethresh = "#"
myTfFunction = TfLogisticGrowth(minimum, maximum, yintercept, lowerthresh, valbelowthresh, upperthresh, valabovethresh)
# Set evaluation scale
fromscale = 1
toscale = 10
# Run RescaleByFunction
outRescale = RescaleByFunction(inRaster, myTfFunction, fromscale, toscale)
# Save the output
outRescale.save("c:/sapyexamples/rescaletflg2")