OWTranspose: Add a new widget

Orange/widgets/data/owtranspose.py

@@ -0,0 +1,117 @@
+from itertools import chain
+
+from AnyQt.QtCore import Qt
+
+from Orange.data import Table, ContinuousVariable, DiscreteVariable
+from Orange.widgets.settings import (Setting, ContextSetting,
+                                     PerfectDomainContextHandler)
+from Orange.widgets.utils import itemmodels
+from Orange.widgets.widget import OWWidget, Msg
+from Orange.widgets import gui
+
+
+class OWTranspose(OWWidget):
+    name = "Transpose"
+    description = "Transpose data table."
+    icon = "icons/Transpose.svg"
+    priority = 2000
+
+    inputs = [("Data", Table, "set_data")]
+    outputs = [("Data", Table)]
+
+    resizing_enabled = False
+    want_main_area = False
+
+    settingsHandler = PerfectDomainContextHandler(metas_in_res=True)
+    feature_names_column = ContextSetting("None")
+    class_variable_index = ContextSetting(0)
+    auto_apply = Setting(True)
+
+    class Error(OWWidget.Error):
+        value_error = Msg("{}")
+
+    def __init__(self):
+        super().__init__()
+        self.data = None
+
+        # GUI
+        options = dict(callback=self.apply, orientation=Qt.Horizontal,
+                       labelWidth=100, contentsLength=12)
+        self.feature_model = itemmodels.VariableListModel()
+        self.feature_combo = gui.comboBox(
+            self.controlArea, self, "feature_names_column",
+            box="Create feature names from", sendSelectedValue=True, **options)
+        self.feature_combo.setModel(self.feature_model)
+
+        self.class_model = itemmodels.VariableListModel()
+        self.class_combo = gui.comboBox(
+            self.controlArea, self, "class_variable_index",
+            box="Class variable as", **options)
+        self.class_combo.setModel(self.class_model)
+
+        self.apply_button = gui.auto_commit(
+            self.controlArea, self, "auto_apply", "&Apply",
+            box=False, commit=self.apply)
+
+    def set_data(self, data):
+        self.closeContext()
+        self.data = data
+        self.update_controls()
+        self.openContext(data)
+        self.apply()
+
+    def update_controls(self):
+        self.feature_model[:] = ["None"]
+        self.class_model[:] = ["None"]
+        self.feature_names_column = "None"
+        if self.data:
+            self.feature_model[:] += list(self.data.domain.metas)
+            if self.data.domain.metas:
+                self.feature_names_column = self.data.domain.metas[0].name
+            names = chain.from_iterable(
+                list(a.attributes.keys()) for a in self.data.domain.attributes)
+            variables = chain.from_iterable(
+                (DiscreteVariable(name), ContinuousVariable(name))
+                for name in sorted(set(names)))
+            self.class_model[:] += list(variables)
+        self.class_variable_index = min(2, len(self.class_model[:])) - 1
+
+    def apply(self):
+        self.clear_messages()
+        transposed = None
+        if self.data:
+            options = dict()
+            if self.feature_names_column != "None":
+                options["feature_names_column"] = self.feature_names_column
+            class_var = self.class_model[self.class_variable_index]
+            if class_var != "None":
+                options["class_name"] = class_var.name
+                options["class_type"] = "d" if class_var.is_discrete else "c"
+
+            try:
+                transposed = Table.transpose(self.data, **options)
+            except ValueError as e:
+                self.Error.value_error(e)
+        self.send("Data", transposed)
+
+    def send_report(self):
+        class_var = self.class_model[self.class_variable_index] \
+            if len(self.class_model) else "None"
+        self.report_items(
+            "", [("Create feature names from", self.feature_names_column),
+                 ("Class variable as", class_var)])
+        if self.data:
+            self.report_data("Data", self.data)
+
+
+if __name__ == "__main__":
+    from PyQt4.QtGui import QApplication
+
+    app = QApplication([])
+    ow = OWTranspose()
+    d = Table("zoo")
+    d.domain.attributes[0].attributes = {"key": "value"}
+    ow.set_data(d)
+    ow.show()
+    app.exec_()
+    ow.saveSettings()