Differences

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--- transformations:keeptop [2014/10/25 17:19] – created dmitry
+++ transformations:keeptop [2021/07/19 02:12] – [Examples] craigt
@@ Line 1: / Line 1: @@
-===== Keep Top Rows =====
+{{ transformations:TrimTableAction.png}}
+====== TRIM TABLE ======
+Category: Transform / Filters\\
-This transformation leaves only first N rows and removes all other rows.
+\\
+=====Description=====
+This action keeps or removes the first or last N rows.\\
-If you need to remove bottom rows -- add line numbers using [[transformations:enumerate|Enumerate Rows]], sort backwards by row numbers using [[transformations:sort|Sort]] and then apply Keep Top Rows.
+\\
+=====Use cases=====
+Keep only the top N significant items (e.g. top 10 products by sales volume) for a report or dashboard.
+Reduce the size of a larger dataset to a specific number of rows during the initial build of a workflow.  Remove or disable the //Trim table// action when the workflow is complete, to process the entire dataset.
+Remove extraneous metadata from the top or bottom of a dataset.\\
+\\
+=====Action settings=====
+^Setting ^Description ^
+|Keep only/Remove|Select whether N number of rows will be kept or removed.|
+|Top/Bottom|Select whether the rows at the top or bottom of the table will be kept/removed.|
+|N rows<sup>*</sup>|Enter/Select the number of rows to keep/remove.|
+<sup>*</sup> Setting can be specified using a [[:parameters|parameter]].
+\\
+=====Examples=====
+**Example:** Keep the top three longest rivers.\\
+\\
+**Table:** The longest rivers in the world (in descending order by length)
+^River  ^Length (km)  ^Continent  ^
+| Nile  |  6650|Africa  |
+| Amazon  |  6400|South America  |
+| Yangtze  |  6300|Asia  |
+| Mississippi  |  6275|North America  |
+| Yenisei  |  5539|Asia  |
+| Yellow River  |  5464|Asia  |
+| Ob  |  5410|Asia  |
+| Paraná  |  4880|South America  |
+\\
+**Action parameters:**
+> Keep or Remove is "Keep"
+> Top or Bottom is "Top"
+> Number of rows is "3"
+\\
+**Result table:**
+^River  ^Length (km)  ^Continent  ^
+| Nile  |  6650|Africa  |
+| Amazon  |  6400|South America  |
+| Yangtze  |  6300|Asia  |
+\\
+====Community examples====
+  * [[https://community.easymorph.com/t//1312/2|A way to obtain all positions of a char in text]] ([[https://community.easymorph.com/uploads/short-url/2lIBiIZXyCaizzyOl1nTkfleYfL.morph|Project]]; Module: //Main//; Group: //Tab 1//; Table: //Table 2//; Action position: //3//)
+  * [[https://community.easymorph.com/t//1870/4|Send email - Add table extract to outlook email message]] ([[https://community.easymorph.com/uploads/short-url/xnfDuDCTN6iJgA4pEcQQsRIZET3.morph|Project]]; Module: //Main//; Group: //Tab 1//; Table: //Input dataset with prepended headers row//; Action position: //2//)
+  * [[https://community.easymorph.com/t//1972/2|Read Data with two line header]] ([[https://community.easymorph.com/uploads/short-url/4YFQxslIv3pmgtF2eRywf4wpcFQ.morph|Project]]; Module: //Main//; Group: //Tab 1//; Table: //Read, Mark groups//; Action position: //2//)
+  * [[https://community.easymorph.com/t//2185/4|Transform parsed JSON to right format]] ([[https://community.easymorph.com/uploads/short-url/z1JsbbyueYletNwNg1VlSef2C4C.morph|Project]]; Module: //Main//; Group: //Group 1//; Table: //Imported table 1.dset//; Action position: //4//)
+\\
+=====See also=====
+  * [[transformations:keepremovematching|Keep/remove matching]]
+  * [[transformations:trimbycondition|Trim table by condition]]