feat: removeDuplicates function

2 files changed, 35 insertions, 1 deletions

diff --git a/src/index.ts b/src/index.ts
index d705527..d69546d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -8,7 +8,14 @@ import {
 } from './lib/locate';
 import { show, head, tail, showAll } from './lib/display';
 import { getSize, info } from './lib/info';
-import { flatten, fromJSON, fromCSV, searchValue, sort } from './lib/data';
+import {
+  flatten,
+  fromJSON,
+  fromCSV,
+  searchValue,
+  sort,
+  removeDuplicates
+} from './lib/data';
 import { toJSON, toCSV } from './lib/export';
 import { isArrayOfType, range, flattenJSON } from './helpers/arrayFunctions';
 
@@ -86,6 +93,7 @@ class Izuku {
   public toJSON = toJSON;
   public toCSV = toCSV;
   public sort = sort;
+  public removeDuplicates = removeDuplicates;
 }
 
 class Frame extends Izuku {
diff --git a/src/lib/data.ts b/src/lib/data.ts
index 480c309..c6ee585 100644
--- a/src/lib/data.ts
+++ b/src/lib/data.ts
@@ -230,3 +230,29 @@ export function sort(
   this.rowdata = sorted;
   return this;
 }
+
+/**
+ * removeDuplicates - removes the duplicate rows from a column
+ * @param column: the column index or column name
+ * @returns the rowdata without duplicates
+ */
+export function removeDuplicates(this: Frame, column: string | number): Frame {
+  const columnIndex =
+    typeof column === 'number' ? column : this.columns.indexOf(column);
+  if (columnIndex === -1) {
+    throw new Error('Invalid column index');
+  }
+  const rowdata = this.rowdata;
+
+  // remove the duplicates from rowdata based on column index
+  const unique = rowdata.filter((row: any[], index: number) => {
+    for (let i = 0; i < index; i++) {
+      if (row[columnIndex] === rowdata[i][columnIndex]) {
+        return false;
+      }
+    }
+    return true;
+  });
+  this.rowdata = unique;
+  return this;
+}