Differences

This shows you the differences between two versions of the page.

--- lesson_7 [2019/08/13 16:58]
argemiro
+++ lesson_7 [2020/02/11 21:51]
hermann
@@ Line 1: / Line 1: @@
-=====LESSON 7: Calculating a lookup table using algebraic/logical expression involving tables and values=====
+{{ :logo_logo.png?400 |}}
+\\
+\\
+====LESSON 7: Creating a new column and retrieving a data column from tables====
+\\
+  * To create a new column in a given table we must open all the files that will be used to retrieve data from. Click on the Input/Output tab from the library window and grab three [[Load Lookup Table]] Functors and one [[Load Table]] placing them on the sketch. Open the [[Load Lookup Table]] functors and load the files ''1999_production_value.csv'', ''1999_harvested_area.csv'' and ''1999_production.csv'' from the folder ''Guidebook_Dinamica_5\Database\Tables\''. Next, open [[Load Table]] and load ''IBGE_crop_information_uptated.csv''.
+\\
+\\
+{{ :imagem43.png?200 |}}
+\\
+\\
+  * Now we can create a new column merge between the ''1999_harvested_area.csv'' and ''1999_production.csv'' files. On the Input/Output tab, grab an [[Add Table Column]] and place it on the sketch. Connect the [[Load Lookup Table]] which contains the file ''1999_harvested_area.csv'' to [[Add Table Column]], selecting __Table__ as an input port. On the Functor Editor window, write a name for the created column (e.g. “production_value”).
+\\
+\\
+<note important>
+The position where the new column is inserted determines whether the new column is a key or data column.
+</note>
+\\
+\\
+{{ :imagem44.png?500 |}}
+\\
+\\
+  * Connect the [[Load Lookup Table]] which contains the file ''1999_production.csv'' to [[Add Table Column]], the __Column Values__ port will be automatically assigned as an input port.
+\\
+  * Add another [[Add Table Column]] to the sketch, assign the output of the previous [[Add Table Column]] to the __Table__ input port of the recently added functor. Connect the [[Load Lookup Table]] with ''1999_production_value.csv'' to the new [[Add Table Column]]. In the Functor Editor window, choose a name for the created column (e.g. "production").
+\\
+  * Add a [[Set Table By Key]] to the sketch, assign the output of [[Add Table Column]] to the __Subtable__ input port of [[Set Table By Key]] and the [[Load Table]] with ''IBGE_crop_information_uptated.csv'' to the __Table__ port. In the Functor Editor window, enter ''1999'' as the key identifying the sub-table that will be updated or inserted. Additionally, toggle the __Ignore Column Names__ flag in the Functor Editor Window.
+\\
+  * To save the result to a file, place a [[Save Table]] on the sketch, browse to ''Guidebook_Dinamica_5\Models\Set_2\basics\'' and write the file name (e.g. ''IBGE_crop_information_complete'').
+\\
+  * Click on the layout tool Execute Layout. Your final model should be similar to the one below:
+\\
+\\
+{{ :imagem45.png?500 |}}
+\\
+\\
+  * Save and run the model. Select the [[Save Table]] functor and click on the eye button to open the resulting table.
+\\
+\\
+{{ :imagem46.png?500 |}}
+\\
+\\
+----
+Using the table generated previously, we would like to demonstrate how to retrieve a data column from it.
+\\
+\\
+  * Grab a [[Load Table]], placing it on the sketch. Double click it and open the file generated in last step (e.g. ''IBGE_crop_information_complete.csv'').
+\\
+\\
+{{ :imagem47.png?500 |}}
+\\
+\\
+  * To retrieve a data column corresponding to the harvested area, we will use [[Get Table Column]]. Connect the [[Load Table]] to [[Get Table Column]]. In the input __Column Index or Name__ of the Functor Editor window, insert the index of the column to be retrieved (“3” or “harvested area”).
+\\
+\\
+{{ :imagem48.png?500 |}}
+\\
+\\
+  * Now, we can retrieve the harvested area per crop corresponding to the year of 2004.  For this, grab a [[Get Table from Key]] and place it on the sketch. Connect [[Get Table Column]] to [[Get Table from Key]]. In the input __Keys__ of the Functor Editor window, insert the year you want to retrieve the harvested area per crop (in this example, “2004”).
+\\
+\\
+{{ :imagem49.png?500 |}}
+\\
+\\
+  * Grab a [[Save Table]] and place it on the sketch. Connect [[Get Table From Key]] and [[Save Table]]. The final model should have the following structure:
+\\
+\\
+{{ :imagem50.png?500 |}}
+\\
+\\
+  * To save the result to a file, edit [[Save Table]], browse to ''GuideBook_Dinamica_5\Models\Set_2\basics\ Get_Table_from_Key'' and write the file name (e.g. IBGE_crop_information_update).
+\\
+\\
+{{ :imagem51.png?500 |}}
+\\
+\\
+  * Save and run the model. To see the resulting table, click on eye button of [[Save Table]]. This functor output is a table that looks like this:
+\\
+\\
+{{ :imagem53.png?300 |}}
+\\
+\\
+==== Congratulations, you have successfully completed this lesson! ====
+\\
+☞[[:lesson_8 | Next Lesson]]
+\\
+☞[[:guidebook_start| Back to Guidebook Start]]