title: No bars shown in R ggplot Gantt chart
body: <p>I have the following dataset as source:</p>
  
  <pre><code>structure(list(JobName = structure(c(1L, 1L, 1L, 2L, 2L, 2L), .Label = ("ATLAS_Admin_DeployClientDatabase", "ATLAS_Admin_ParseMasterCubeDatabase", ATLAS_Admin_xBackup_DeleteOldTable", "BDC_DatabaseMaintenanceJob_ALL_DATABASES", collection_set_1_noncached_collect_and_upload", "CoreX_SAP_B23_dreprecated", CoreXBI_ETL_1014_01Stage", "CoreXBI_ETL_1014_02DWH_Cube", "CoreXBI_ETL_1114_02DWH_Cube", "CoreXBI_ETL_1294_B23", CoreXBI_ETL_AutoTest", "Cycle_Log", "Delphi DEV Load", "Delphi DEV Monthly", mdw_purge_data_[Z_MAS_MDW]", "QA_CoreXBI_ETL_1010", "QA_CoreXBI_ETL_1294", Shrink_the_Logs", "SSIS Server Maintenance Job", "syspolicy_purge_history", sysutility_get_cache_tables_data_into_aggregate_tables_daily", "sysutility_get_cache_tables_data_into_aggregate_tables_hourly", "sysutility_get_views_data_into_cache_tables", "Z_MAS_ADMIN_ALRS", "Z_MAS_ADMIN_Backup_AMOTables", "Z_MAS_ADMIN_Check_Cube_Space", "Z_MAS_ADMIN_Check_Disk_Space", "Z_MAS_ADMIN_Extract_Job_History", "Z_MAS_ADMIN_Monitoring", "Z_MAS_MaintenancePlan.weekly_bak_clean", "Z_MICE_System_Database_Backup_weekly"), class = "factor"), RunDateTime = tructure(c(1478788776, 1479292645, 1479307979, 1479292220, 1479307916, 479314398), class = c("POSIXct", "POSIXt"), tzone = ""), StartWeekday = tructure(c(5L, 7L, 7L, 7L, 7L, 7L), .Label = c("Friday", "Monday", Saturday", "Sunday", "Thursday", "Tuesday", "Wednesday"), class = "factor"), tartTime = structure(c(-2209108824, -2209123355, -2209108021, -2209123780, 2209108084, -2209101602), class = c("POSIXct", "POSIXt"), tzone = ""), ndRunDateTime = structure(c(1478790159, 1479294190, 1479309546, 1479292284, 479307977, 1479314459), class = c("POSIXct", "POSIXt"), tzone = ""), ndWeekday = structure(c(5L, 7L, 7L, 7L, 7L, 7L), .Label = c("Friday", Monday", "Saturday", "Sunday", "Thursday", "Tuesday", "Wednesday"), class = factor"), EndTime = structure(c(-2209107441, -2209121810, -2209106454, 2209123716, -2209108023, -2209101541), class = c("POSIXct", "POSIXt"), tzone  "")), .Names = c("JobName", "RunDateTime", "StartWeekday", StartTime", "EndRunDateTime", "EndWeekday", "EndTime"), row.names = c(NA, L), class = "data.frame")
  </code></pre>
  
  <p>Now I use the following script to create a Gantt chart out of data that should show me the durations of the different jobs in the timeline.</p>
  
  <pre><code>library(reshape2)
  vars &lt;- c("RunDateTime", "EndRunDateTime", "StartTime", "EndTime")
  dataset[vars] &lt;- lapply(dataset[vars], as.POSIXct, format = "%Y-%m-%dT%H:%M:%S")
  df &lt;- with(dataset, data.frame(name = JobName, start = RunDateTime, end = EndRunDateTime))
  mdfr &lt;- melt(df, measure.vars = c("start", "end"))
  
  library(ggplot2)
  ggplot(mdfr, aes( x = value, y = name, color = variable))
  geom_line(size = 6)
  xlab(NULL)
  ylab(NULL)
  </code></pre>
  
  <p>My problem is, that I get a chart with JobNames on the y-axis and DateTimes on the x-axis, but no values or bars in it.</p>
  
  <p><a href="https://i.stack.imgur.com/4pZjr.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/4pZjr.jpg" alt="enter image description here"></a></p>
  
  <p>Any idea what it's about?</p>
  
  <p>EDIT: Next problem is now, that it connects the very first start time with the very last end time...</p>
  
  <p><img src="https://i.stack.imgur.com/T7Ucx.jpg" alt="Gantt chart with connected times"></p>