# Initiation and working with existing models
Note: GsaGH requires at least GSA build 10.1.60 or above to run.
This tutorial will demonstrate how to work with existing GSA models in GsaGH. The methods here are applicable to any project type.
The key outcomes are:
- Open existing GSA models with GsaGH
- Extract geometry from the existing model
- Extract section properties used in the existing model
- Extract material properties used in the existing model
# Part 1
# Opening existing models
To open an existing model, use the Open model 
component from the Model tab.
Click on the Open button and select the GSA model to open.
Go to the model tab and select Get model geometry 
.
Drag the GSA output from the Open model component into the GSA input of the Get model geometry component.
The imported geometry is shown to the left of the screen.
The Get model geometry component gives a summary of the types of elements and members used in this GSA model, and the units used to import the model. Text filters following the standard GSA conventions can be used to separate out elements or members by various criteria. Ex., PB1 to PB3 will filter out members of properties PB1, 2 and 3.
# Extracting 1D properties
The outputs from the Get geometry component give the various GSA entities like nodes, elements, members along with their IDs.
In the Parameters tab, select the relevant parameter to plug in to the outputs of the Get geometry component.
Another layer of information can be extracted from the GSA model. Go to Explorer pane > Section library in GSA to view a table of your properties.
To extract these within GsaGH:
In Grasshopper, select the Model tab.
Click Get model properties
.Connect the GSA model to this input to get all the beam, area and volume (PB, PA, PV) properties defined in the model.
To extract yet another layer of information, go to Properties and select the Edit section component, to drag on to the canvas.
Connect the PB output from the Get model properties component into the the PB input of this component to extract all information from this profile.
To edit one of these existing definitions, (in this example ID), enter a new property value and plug in the relevant input of the Edit section component.
Note: This functionality of editing or overwriting existing values is possible with all Edit components in GsaGH.
# Part 2
# Extracting 2D properties
In this example we will work with 2D members within a GSA model in GsaGH.
In the Geometry tab, select Edit 2D member 
.
In the Properties tab select the Edit 2d properties 
component to extract another layer of information about each property.
To cross reference the information in Grasshopper with GSA, go to GSA and refer to Members in the Explorer pane.
Tip: Right click in the centre of the Edit 2d property component to change the units.
# Material properties
In Grasshopper select the Edit material component 
from the Properties tab to look at this parameter in more detail.
Select Material properties 
from the Properties tab.
Connect to a material input, and view your summaries in the text window.
To check the values with GSA, go to Explorer pane > Materials > Advanced > Material properties.
Tip: Right click on the Material properties component to change the units for, example, stress, density or temperature.