add Cut ops

examples/highfreq/highfreq_handler.py

@@ -62,9 +62,9 @@ class HighFreqHandler(DataHandlerLP):
         def get_normalized_price_feature(price_field, shift=0):
             """Get normalized price feature ops"""
             if shift == 0:
-                template_norm = "{0}/Ref(DayLast({1}), 240)"
+                template_norm = "Cut({0}/Ref(DayLast({1}), 240), 240, None)"
             else:
-                template_norm = "Ref({0}, " + str(shift) + ")/Ref(DayLast({1}), 240)"
+                template_norm = "Cut(Ref({0}, " + str(shift) + ")/Ref(DayLast({1}), 240), 240, None)"
 
             feature_ops = template_norm.format(
                 template_if.format(
@@ -90,7 +90,7 @@ class HighFreqHandler(DataHandlerLP):
         names += ["$open_1", "$high_1", "$low_1", "$close_1", "$vwap_1"]
 
         fields += [
-            "{0}/Ref(DayLast(Mean({0}, 7200)), 240)".format(
+            "Cut({0}/Ref(DayLast(Mean({0}, 7200)), 240), 240, None)".format(
                 "If(IsNull({0}), 0, If(Or(Gt({1}, Mul(1.001, {3})), Lt({1}, Mul(0.999, {2}))), 0, {0}))".format(
                     template_paused.format("$volume"),
                     template_paused.format(simpson_vwap),
@@ -101,7 +101,7 @@ class HighFreqHandler(DataHandlerLP):
         ]
         names += ["$volume"]
         fields += [
-            "Ref({0}, 240)/Ref(DayLast(Mean({0}, 7200)), 240)".format(
+            "Cut(Ref({0}, 240)/Ref(DayLast(Mean({0}, 7200)), 240), 240, None)".format(
                 "If(IsNull({0}), 0, If(Or(Gt({1}, Mul(1.001, {3})), Lt({1}, Mul(0.999, {2}))), 0, {0}))".format(
                     template_paused.format("$volume"),
                     template_paused.format(simpson_vwap),
@@ -112,7 +112,7 @@ class HighFreqHandler(DataHandlerLP):
         ]
         names += ["$volume_1"]
 
-        fields += [template_paused.format("Date($close)")]
+        fields += ["Cut({0}, 240, None)".format(template_paused.format("Date($close)"))]
         names += ["date"]
         return fields, names
 
@@ -149,18 +149,20 @@ class HighFreqBacktestHandler(DataHandler):
         # Because there is no vwap field in the yahoo data, a method similar to Simpson integration is used to approximate vwap
         simpson_vwap = "($open + 2*$high + 2*$low + $close)/6"
         fields += [
-            template_fillnan.format(template_paused.format("$close")),
+            "Cut({0}, 240, None)".format(template_fillnan.format(template_paused.format("$close"))),
         ]
         names += ["$close0"]
         fields += [
-            template_if.format(
-                template_fillnan.format(template_paused.format("$close")),
-                template_paused.format(simpson_vwap),
+            "Cut({0}, 240, None)".format(
+                template_if.format(
+                    template_fillnan.format(template_paused.format("$close")),
+                    template_paused.format(simpson_vwap),
+                )
             )
         ]
         names += ["$vwap0"]
         fields += [
-            "If(IsNull({0}), 0, If(Or(Gt({1}, Mul(1.001, {3})), Lt({1}, Mul(0.999, {2}))), 0, {0}))".format(
+            "Cut(If(IsNull({0}), 0, If(Or(Gt({1}, Mul(1.001, {3})), Lt({1}, Mul(0.999, {2}))), 0, {0})), 240, None)".format(
                 template_paused.format("$volume"),
                 template_paused.format(simpson_vwap),
                 template_paused.format("$low"),

examples/highfreq/highfreq_ops.py

@@ -54,3 +54,25 @@ class IsNull(ElemOperator):
     def _load_internal(self, instrument, start_index, end_index, freq):
         series = self.feature.load(instrument, start_index, end_index, freq)
         return series.isnull()
+
+
+class Cut(ElemOperator):
+    def __init__(self, feature, l=None, r=None):
+        self.l = l
+        self.r = r
+        if (self.l != None and self.l <= 0) or (self.r != None and self.r >= 0):
+            raise ValueError("Cut operator l shoud > 0 and r should < 0")
+
+        super(Cut, self).__init__(feature)
+
+    def _load_internal(self, instrument, start_index, end_index, freq):
+        series = self.feature.load(instrument, start_index, end_index, freq)
+        return series.iloc[self.l : self.r]
+
+    def get_extended_window_size(self):
+        ll = 0 if self.l == None else self.l
+        rr = 0 if self.r == None else abs(self.r)
+        lft_etd, rght_etd = self.feature.get_extended_window_size()
+        lft_etd = lft_etd + ll
+        rght_etd = rght_etd + rr
+        return lft_etd, rght_etd

examples/highfreq/workflow.py

@@ -24,17 +24,17 @@ from qlib.data.ops import Operators
 from qlib.data.data import Cal
 from qlib.tests.data import GetData
 
-from highfreq_ops import get_calendar_day, DayLast, FFillNan, BFillNan, Date, Select, IsNull
+from highfreq_ops import get_calendar_day, DayLast, FFillNan, BFillNan, Date, Select, IsNull, Cut
 
 
 class HighfreqWorkflow(object):
 
-    SPEC_CONF = {"custom_ops": [DayLast, FFillNan, BFillNan, Date, Select, IsNull], "expression_cache": None}
+    SPEC_CONF = {"custom_ops": [DayLast, FFillNan, BFillNan, Date, Select, IsNull, Cut], "expression_cache": None}
 
-    MARKET = "all"
+    MARKET = ["SH600004"]
     BENCHMARK = "SH000300"
 
-    start_time = "2020-09-14 00:00:00"
+    start_time = "2020-09-15 00:00:00"
     end_time = "2021-01-18 16:00:00"
     train_end_time = "2020-11-30 16:00:00"
     test_start_time = "2020-12-01 00:00:00"