### Example Output Band Calculations

Source: https://doc.arcgis.com/en/arcgis-online/analyze/spectral-conversion-function.htm

Demonstrates how the example conversion matrix is applied to input bands to calculate output bands for a pseudo-color image.

```plaintext
Output band 1 = (0.1 * InputBand1) + (0.9 * InputBand2) +(0.0 * InputBand3)
Output band 2 = (0.3 * InputBand1) + (0.0 * InputBand2) +(0.7 * InputBand3)
Output band 3 = (0.1 * InputBand1) + (0.1 * InputBand2) +(0.8 * InputBand3)
```

--------------------------------

### Metadata JSON Input Example

Source: https://doc.arcgis.com/en/arcgis-online/analyze/key-metadata-function.htm

Example of a JSON string structure used to define key metadata, including cloud cover and specific band properties.

```json
{
     "CloudCover": 4,
     "BandProperties":[
          {
               "BandName": "Blue",
               "WavelengthMin": 445,
               "WavelengthMax": 516
         },
         {
              "BandName": "Green",
              "WavelengthMin": 506,
              "WavelengthMax": 595
         },

    ]
}
```

--------------------------------

### Example: Calculate days between inspection and installation dates

Source: https://doc.arcgis.com/en/arcgis-online/manage-data/calculate-fields.htm

Demonstrates calculating the number of days between an inspection date and an installation date using date fields. The result is a whole number representing days.

```SQL
<InspectionDateField> - <InstallationDateField> = 122 (days)
```

--------------------------------

### Example: Calculate days between date literal and field

Source: https://doc.arcgis.com/en/arcgis-online/manage-data/calculate-fields.htm

Calculates the number of days between a fixed inspection date literal and a specific installation date field.

```SQL
DATE'10/1/2015' - <InstallationDateField> = 122 (days)
```

--------------------------------

### Initialize ArcPy in a notebook

Source: https://doc.arcgis.com/en/arcgis-online/reference/use-arcpy-in-your-notebook.htm

Import the ArcPy library and verify the installed version.

```python
import arcpy
arcpy.GetInstallInfo()['Version']
```

--------------------------------

### Open a service by URL

Source: https://doc.arcgis.com/en/arcgis-online/reference/use-url-parameters-scenes.htm

Use the ?url=<service> parameter to load a specific service directly into a scene. This example loads a building service for Portland, Oregon.

```url
https://www.maps.arcgis.com/home/webscene/viewer.html?url=https://tiles.arcgis.com/tiles/P3ePLMYs2RVChkJx/arcgis/rest/services/Buildings_Portland/SceneServer
```

--------------------------------

### Example: Calculate days between date field and literal

Source: https://doc.arcgis.com/en/arcgis-online/manage-data/calculate-fields.htm

Calculates the number of days between a specific inspection date field and a fixed installation date literal.

```SQL
<InspectionDateField> - DATE'6/1/2015' = 122 (days)
```

--------------------------------

### Extract Substring from Start

Source: https://doc.arcgis.com/en/arcgis-online/manage-data/calculate-fields.htm

Returns a portion of a string starting from a specified index for a given length. The start index is 1-based.

```SQL
SUBSTRING('Sailboat', 1, 4)
```

--------------------------------

### Plot Spatially Enabled DataFrame (Quickstart)

Source: https://doc.arcgis.com/en/arcgis-online/create-maps/use-python-code-snippets.htm

Generates a quick plot of a spatially enabled DataFrame, showing the spatial distribution of features.

```python
from arcgis.gis import GIS

gis = GIS('home')
# Assuming 'sdf' is your spatially enabled DataFrame
sdf.plot()
```

--------------------------------

### Install a specific version of a package using conda

Source: https://doc.arcgis.com/en/arcgis-online/create-maps/specify-the-runtime-of-a-notebook.htm

Specify the desired version of a package when installing it. Remember to restart the kernel after installation.

```bash
!conda install --yes <package name>==1.6
```

--------------------------------

### Create and set scratch geodatabase workspace

Source: https://doc.arcgis.com/en/arcgis-online/create-maps/work-with-content-in-a-user-workspace.htm

Use this code to create a scratch file geodatabase if it doesn't exist and set it as the scratch workspace environment. This is useful for temporary output data.

```python
import arcpy
if not arcpy.Exists('/arcgis/home/scratch.gdb'):
    arcpy.management.CreateFileGDB('/arcgis/home','scratch.gdb')
arcpy.env.scratchWorkspace = '/arcgis/home/scratch.gdb'
```

```python
print(arcpy.env.scratchGDB)
```

--------------------------------

### Install a package using conda

Source: https://doc.arcgis.com/en/arcgis-online/create-maps/specify-the-runtime-of-a-notebook.htm

Use this command to install a package like scrapy. You must restart the kernel after installation for the package to be available.

```bash
!conda install --yes scrapy
```

--------------------------------

### Create and set scratch folder workspace

Source: https://doc.arcgis.com/en/arcgis-online/create-maps/work-with-content-in-a-user-workspace.htm

Use this code to create a folder for a scratch workspace if it doesn't exist and set it as the scratch workspace environment. This is useful for temporary output data.

```python
import arcpy
if not arcpy.Exists('/arcgis/home/scratch'):
    arcpy.management.CreateFolder('/arcgis/home', 'scratch')
arcpy.env.scratchWorkspace = '/arcgis/home/scratch'
```

```python
print(arcpy.env.scratchFolder)
```