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====== Grid_Wizard ======

The **Grid Wizard** interpolates data from a point-based layer into a grid file. The resulting grid file represents the same space as the point-based layer as a grid of equally sized squares, which can then be styled appropriately.

This dialog consists of 4 steps:  
  * Step 1 - Choose the Source Layer
  * Step 2 - Select the column to be interpolated
  * Step 3 - Configure the grid options
  * Step 4 - Save the Results

===== Video Overview =====
{{#ev:youtubehd|j5d9JgHu0rY|720||How to use the Grid Wizard.}}

[[Category:Processing Data]] [[Category:Articles with Video]]

===== Step 1 - Choose the Source Layer =====
Step 1 of the Grid Wizard allows users to select which point-based layer to interpolate data from. 

If your layer has certain features that have been selected on the **Select Features** tab, you may also check the **Only buffer the currently selected features on this layer** checkbox.

===== Step 2 - Select the column to be interpolated =====
Select a data column to use to interpolate for the grid. You can view the selected column's data before proceeding further.

===== Step 3 - Configure the grid options =====
In Step 3, we choose which algorithm to interpolate from. Currently, we only support Inverse Distance Weighting, but more will be added in future updates. The power is how much emphasis a point will place based on the distance of other points around it. A higher power means a higher emphasis. Generally, this is kept at 2. Our search radius determines at what distance a point will not affect a single cell. If there are no points within that distance, the value of the data set that we are generating the grid file on will be zero. We then determine how large, or small, each cell will be. Essentially, this is the grid's resolution so choosing an appropriate size is completely up to you.

===== Step 4 - Save the Results =====
Like all other Tools wizards, this step allows users to choose how they want the wizard results to be saved.  Users can choose to **Add to Map** and specify the desired layer name, or choose to **Output to File**.  If **Output to File** is chosen, the user must select an existing or new file to save the results into.

=====Viewing the Grid File=====
Now that we have our grid file generated, we can see the data for each of the grid cells, either by selecting the cells and viewing the data on the Feature Information panel, or by using the view data function on the newly created layer. Now that we have our data interpolated, we can now set up a new style to make visual use out of the grid. Right-click on the grid layer and add a new [[Class Break Style|class break style]]. We select the CellValue column name and then use auto generate to set up different colors for each range of numbers. Now we have a meaningful grid file that visually shows our data.

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