update tablesaw to 0.37.3, use pivot method

uwemaurer · uwemaurer · commit 810f99f17f80 · 2020-01-28T10:05:15.000+01:00
diff --git a/build.gradle b/build.gradle
@@ -9,7 +9,7 @@ repositories {
 }
 
 dependencies {
-  compile 'tech.tablesaw:tablesaw-core:0.30.1'
+  compile 'tech.tablesaw:tablesaw-core:0.37.3'
 
   compile 'joinery:joinery-dataframe:1.9'
   // For the CSV import joinery needs this dependency too:
diff --git a/src/main/java/test_dataframes/TestTablesaw.java b/src/main/java/test_dataframes/TestTablesaw.java
@@ -5,7 +5,6 @@
 import tech.tablesaw.api.DoubleColumn;
 import tech.tablesaw.api.StringColumn;
 import tech.tablesaw.api.Table;
-import tech.tablesaw.columns.Column;
 import tech.tablesaw.io.csv.CsvReadOptions;
 
 import com.google.common.base.Stopwatch;
@@ -32,32 +31,11 @@ public static void main(String[] args) throws Exception {
         System.out.println(cities.print(10));
 
         // Need to transpose/pivot now too
-        // Next version of tablesaw will make this a one-liner!
-        Table finalTable = Table.create("final");
-        finalTable.addColumns(StringColumn.create("key"));
-        cities.forEach(row -> {
-            int year = row.getShort("TIME");
-            String yearStr = Integer.toString(year);
-            String key = row.getString("CITIES") + ":" + row.getString("INDIC_UR");
-            double value = row.getDouble("Mean [Value]");
-            if (!finalTable.columnNames().contains(yearStr)) {
-                DoubleColumn col = DoubleColumn.create(yearStr);
-                // Need to prefill null for rows that exist already.
-                for (int i = 0; i < finalTable.rowCount(); i++) {
-                    col.appendMissing();
-                }
-                finalTable.addColumns(col);
-            }
-            int firstIndex = ((StringColumn)finalTable.column("key")).firstIndexOf(key);
-            if (firstIndex == -1) {
-                firstIndex = finalTable.rowCount();
-                for (Column<?> col : finalTable.columns()) {
-                    col.appendMissing();
-                }
-                ((Column<String>)finalTable.column("key")).set(firstIndex, key);
-            }
-            ((Column<Double>)finalTable.column(yearStr)).set(firstIndex, value);
-        });
+        StringColumn key = filtered.stringColumn("CITIES")
+            .join(":", filtered.stringColumn("INDIC_UR")).setName("key");
+        filtered.addColumns(key);
+        Table finalTable = filtered.pivot("key", "TIME", "Value", mean);
+
         // sortDescendingOn puts N/A values first unfortunately, so let's remove them
         // before determining and printing.
         Table existing2017 = finalTable.dropWhere(finalTable.column("2017").isMissing());

Original file line number	Diff line number	Diff line change
`@@ -9,7 +9,7 @@ repositories {`
`9`	`9`	`}`
`10`	`10`
`11`	`11`	`dependencies {`
`12`		`- compile 'tech.tablesaw:tablesaw-core:0.30.1'`
	`12`	`+ compile 'tech.tablesaw:tablesaw-core:0.37.3'`
`13`	`13`
`14`	`14`	`compile 'joinery:joinery-dataframe:1.9'`
`15`	`15`	`// For the CSV import joinery needs this dependency too:`