If you check the travis.yml file, CI for Go 1.11 version is not there anymore. There's only 1.14, 1.13, 1.12, and it's been updated recently in February. However, The Dockerfile points to building Go 1.11. Maybe try redownloading this source and rewrite part of the Dockerfile to build from 1.13 and start again while this issue is resolved?

language: go

go:
  - 1.14.x
  - 1.13.x
  - 1.12.x
  - master

If you check the travis.yml file, CI for Go 1.11 version is not there anymore. There's only 1.14, 1.13, 1.12, and it's been updated recently in February. However, The Dockerfile points to building Go 1.11. Maybe try redownloading this source and rewrite part of the Dockerfile to build from 1.13 and start again while this issue is resolved?

language: go

go:
  - 1.14.x
  - 1.13.x
  - 1.12.x
  - master

You won't have to rewrite the Dockerfile, it pulls the latest go package in the alpine repo

I digged into Dockerhub, and @oneoneonepig you are right the docker image was last pushed a year ago, while the latest Dockerfile source on this repo added support for 1.11 version. Looks like you'd have to try building this locally instead of using Docker @MilesLin.

I think that is the bug from github.com/kniren/gota which is the package built-in in the container.
I created a sample to demonstrate this issue.

here is the code.

import(
    "github.com/kniren/gota/dataframe"
    "github.com/kniren/gota/series"
)
type TestSt struct {
	Name string
	Score int `dataframe:"Score,int"`
}
data := []TestSt{}
	data = append(data, TestSt{
		Name: "Miles",
		Score: 21,
	})
df := dataframe.LoadStructs(data)
result := series.New(df.Col("Score"), series.Float, "Score")