Implemented some API queries

Author: olekscode

DataFrame-Core.package/DataFrame.class/class/fromXLSX..st

@@ -4,7 +4,7 @@ fromXLSX: pathToFile
 	| file workbook sheet |
 
 	file := FileStream readOnlyFileNamed: pathToFile.
-	workbook := XLSXImporter import file.
+	workbook := XLSXImporter import: file.
 	sheet := workbook worksheets first.
 
 	^ self fromXLSXworksheet: sheet.

DataFrame-Core.package/DataFrame.class/class/fromXLSXworksheet..st

@@ -4,4 +4,5 @@ fromXLSXworksheet: sheet
 	| matrix df |
 
 	matrix := sheet cellValuesAsMatrix.
-	df := self new initializeMatrix: matrix.
+	df := self new initializeMatrix: matrix.
+	^ df

DataFrame-Core.package/DataFrame.class/instance/select.where..st

@@ -0,0 +1,4 @@
+as yet unclassified
+select: colNames where: aBlock
+	
+	^ (self selectAllWhere: aBlock) columns: colNames

DataFrame-Core.package/DataFrame.class/instance/select.where.groupBy.aggregate..st

@@ -0,0 +1,5 @@
+as yet unclassified
+select: colNames where: aBlock groupBy: aColName aggregate: selector
+	
+	^ ((self select: colNames where: aBlock)
+		groupBy: aColName) perform: selector.

DataFrame-Core.package/DataFrame.class/instance/select.with..st

@@ -1,21 +1,18 @@
 enumerating
-select: aBlock with: anArray
+select: aBlock with: testedColumnNames
 
-	( anArray size = 1 ) ifTrue: [ 
-		^ self select: [ :row | 
-			aBlock value: (row atKey: (anArray at: 1)) ] ].
+	| blockStr |
+	blockStr := aBlock asString.
 
-	( anArray size = 2 ) ifTrue: [ 
-		^ self select: [ :row | 
-			aBlock
-				value: (row atKey: (anArray at: 1)) 
-				value: (row atKey: (anArray at: 2)) ] ].
+	"Remove parameters: '[ :x | x > 3 ]' to '[ x > 3 ]'"
+	blockStr := (blockStr
+		copyFrom: (blockStr findString: '|')
+		to: blockStr size).
 
-	( anArray size = 3 ) ifTrue: [ 
-		^ self select: [ :row | 
-			aBlock
-				value: (row atKey: (anArray at: 1)) 
-				value: (row atKey: (anArray at: 2))
-				value: (row atKey: (anArray at: 3)) ] ].
+	testedColumnNames do: [ :eachColName |
+		blockStr := blockStr
+			copyReplaceAll: eachColName
+			with: ('(row atKey: #', eachColName, ')') ].
 
-	Error signal: 'Too many arguments'.
+	blockStr := '[ :row ', blockStr.
+	^ self select: (Compiler evaluate: blockStr)

DataFrame-Core.package/DataFrame.class/instance/selectAllWhere..st

@@ -0,0 +1,10 @@
+as yet unclassified
+selectAllWhere: aBlock
+
+	| testedColumnNames |
+	testedColumnNames := aBlock argumentNames.
+	
+	(self columnNames includesAll: testedColumnNames)
+		ifFalse: [ Error signal: 'All arguments of the where block must correspond to the column names of a data frame' ].
+		
+	^ self select: aBlock with: testedColumnNames