Add the docs about hercules-combine and fix some bugs

README.md

@@ -7,7 +7,8 @@ Powered by [go-git](https://github.com/src-d/go-git) and [Babelfish](https://doc
 There are two tools: `hercules` and `labours.py`. The first is the program
 written in Go which takes a Git repository and runs a Directed Acyclic Graph (DAG) of [analysis tasks](doc/PIPELINE_ITEMS.md).
 The second is the Python script which draws some predefined plots. These two tools are normally used together through
-a pipe. It is possible to write custom analyses using the plugin system.
+a pipe. It is possible to write custom analyses using the plugin system. It is also possible
+to merge several analysis results together.
 
 ![Hercules DAG of Burndown analysis](doc/dag.png)
 <p align="center">The DAG of burndown and couples analyses with UAST diff refining. Generated with <code>hercules -burndown -burndown-people -couples -feature=uast -dry-run -dump-dag doc/dag.dot https://github.com/src-d/hercules</code></p>
@@ -190,6 +191,16 @@ python3 labours.py -m all
 
 Hercules has a plugin system and allows to run custom analyses. See [PLUGINS.md](PLUGINS.md).
 
+### Merging
+
+`hercules-combine` is the tool which joins several analysis results in Protocol Buffers format together. 
+
+```
+hercules -burndown -pb https://github.com/src-d/go-git > go-git.pb
+hercules -burndown -pb https://github.com/src-d/hercules > hercules.pb
+hercules-combine go-git.pb hercules.pb | python3 labours.py -f pb -m project --resample M
+```
+
 ### Bad unicode errors
 
 YAML does not support the whole range of Unicode characters and the parser on `labours.py` side

burndown.go

@@ -260,6 +260,8 @@ func (analyser *BurndownAnalysis) Finalize() interface{} {
 		PeopleHistories:    analyser.peopleHistories,
 		PeopleMatrix:       peopleMatrix,
 		reversedPeopleDict: analyser.reversedPeopleDict,
+		sampling:           analyser.Sampling,
+		granularity:        analyser.Granularity,
 	}
 }
 
@@ -651,8 +653,8 @@ func addBurndownMatrix(matrix [][]int64, granularity, sampling int, daily [][]fl
 }
 
 func (analyser *BurndownAnalysis) serializeText(result *BurndownResult, writer io.Writer) {
-	fmt.Fprintln(writer, "  granularity:", analyser.Granularity)
-	fmt.Fprintln(writer, "  sampling:", analyser.Sampling)
+	fmt.Fprintln(writer, "  granularity:", result.granularity)
+	fmt.Fprintln(writer, "  sampling:", result.sampling)
 	yaml.PrintMatrix(writer, result.GlobalHistory, 2, "project", true)
 	if len(result.FileHistories) > 0 {
 		fmt.Fprintln(writer, "  files:")
@@ -678,8 +680,8 @@ func (analyser *BurndownAnalysis) serializeText(result *BurndownResult, writer i
 
 func (analyser *BurndownAnalysis) serializeBinary(result *BurndownResult, writer io.Writer) error {
 	message := pb.BurndownAnalysisResults{
-		Granularity: int32(analyser.Granularity),
-		Sampling:    int32(analyser.Sampling),
+		Granularity: int32(result.granularity),
+		Sampling:    int32(result.sampling),
 	}
 	if len(result.GlobalHistory) > 0 {
 		message.Project = pb.ToBurndownSparseMatrix(result.GlobalHistory, "project")

burndown_test.go

@@ -315,7 +315,7 @@ func TestBurndownConsumeFinalize(t *testing.T) {
 	}
 }
 
-func TestBurndownAnalysisSerialize(t *testing.T) {
+func TestBurndownSerialize(t *testing.T) {
 	burndown := BurndownAnalysis{
 		Granularity:  30,
 		Sampling:     30,

labours.py

@@ -235,7 +235,7 @@ class ProtobufReader(Reader):
         return list(node.index), self._parse_sparse_matrix(node.matrix)
 
     def get_people_coocc(self):
-        node = self.contents["Couples"].developer_couples
+        node = self.contents["Couples"].people_couples
         return list(node.index), self._parse_sparse_matrix(node.matrix)
 
     def _parse_burndown_matrix(self, matrix):
@@ -281,6 +281,8 @@ def load_burndown(header, name, matrix, resample):
     import pandas
 
     start, last, sampling, granularity = header
+    assert sampling > 0
+    assert granularity >= sampling
     start = datetime.fromtimestamp(start)
     last = datetime.fromtimestamp(last)
     print(name, "lifetime index:", calculate_average_lifetime(matrix))