bugfix/workaround geherating plots: -1 is interpreted as 'invalid value' -...

bugfix/workaround geherating plots: -1 is interpreted as 'invalid value' - filter out all -1 values...

VectoCoreTest/Utils/GraphWriter.cs

@@ -112,8 +112,17 @@ namespace TUGraz.VectoCore.Tests.Utils
 
 					for (var i = 1; i <= yfields.Length; i++) {
 						var yfield = yfields[i - 1];
-						var y = modDataV3.Rows.Cast<DataRow>().Select(v => v.Field<string>(yfield.GetName())).ToArray();
-						var y2 = modDataV22.Rows.Cast<DataRow>().Select(v => v.Field<string>(yfield.GetName())).ToArray();
+						var y =
+							modDataV3.Rows.Cast<DataRow>()
+								.Select(v => v.Field<string>(yfield.GetName()))
+								.Select(v => v == "-1" ? "-1.00001" : v)
+								.ToArray();
+						//y = y.ToArray();
+						var y2 =
+							modDataV22.Rows.Cast<DataRow>()
+								.Select(v => v.Field<string>(yfield.GetName()))
+								.Select(v => v == "-1" ? "-1.00001" : v)
+								.ToArray();
 
 						var values = string.Format("{0}|{1}|{2}|{3}", string.Join(",", x), string.Join(",", y), string.Join(",", x2),
 							string.Join(",", y2));
@@ -127,7 +136,8 @@ namespace TUGraz.VectoCore.Tests.Utils
 							values += string.Format("|{0}|{1}", string.Join(",", x), string.Join(",", y3));
 						}
 
-						values = values.Replace("NaN", "0");
+						values = values.Replace("NaN", "_");
+						//values = values.Replace("-1", "-1.00001");
 						if (values.Length > 14000) {
 							// remove all decimal places to reduce request size
 							values = Regex.Replace(values, @"(\.[0-9]).*?,", "$1,");
@@ -146,6 +156,7 @@ namespace TUGraz.VectoCore.Tests.Utils
 
 		private static Stream CreateGraphStream(string xLabel, string yLabel, int xAxisRange, string values)
 		{
+			// see https://developers.google.com/chart/image/?hl=en for details
 			using (var client = new WebClient()) {
 				var response = client.UploadValues("https://chart.googleapis.com/chart", new NameValueCollection {
 					{ "cht", "lxy" },