BandMaths Operator

BandMaths Operator Description

Overview

Description

This band maths operator can be used to create a product with multiple bands based on mathematical expression.
All products specified as source must have the same width and height, otherwise the operator will fail. The geo-coding information and metadata for the target product is taken from the first source product.

To reference a band of one of the source products within an expression use the following syntax:

sourceProducts#.bandName

Where # means the index of the source product. The index is zero based.
The bands of the first source product (sourceProducts0) can be referenced without this product identifier.

When using this operator from the command-line Graph XML file must be provided in order to specify all parameters. Here is some sample XML of how to use a BandMaths node within a graph:

      <node id="bandMathsNode">
        <operator>BandMaths</operator>
        <sources>
            <sourceProducts>readNode</sourceProducts>
        </sources>
        <parameters>
            <targetBands>
                <targetBand>
                    <name>reflec_13</name>
                    <expression>radiance_13 / (PI * SOLAR_FLUX_13)</expression>
                    <description>TOA reflectance in channel 13</description>
                    <type>float</type>
                    <validExpression>reflec_13 >= 0</validExpression>
                    <noDataValue>-999</noDataValue>
                    <spectralBandIndex>13</spectralBandIndex>
                </targetBand>
                <targetBand>
                    <name>reflec_14</name>
                    <expression>radiance_14 / (PI * SOLAR_FLUX_14)</expression>
                    <description>TOA reflectance in channel 14</description>
                    <type>float</type>
                    <validExpression>reflec_14 >= 0</validExpression>
                    <noDataValue>-999</noDataValue>
                    <spectralBandIndex>14</spectralBandIndex>
                </targetBand>
            </targetBands>
            <variables>
                <variable>
                    <name>SOLAR_FLUX_13</name>
                    <type>float</type>
                    <value>914.18945</value>
                </variable>
                <variable>
                    <name>SOLAR_FLUX_14</name>
                    <type>float</type>
                    <value>882.8275</value>
                </variable>
                 <variable>
                    <name>PI</name>
                    <type>double</type>
                    <value>3.1415</value>
                </variable>
            </variables>
        </parameters>
    </node>
 

Sources

Parameters