Learning Notes

Strings are a slice of bytes, uint8. They are immutable, cannot change a variable's individual bytes. Declaring variable string: aString := "double quoted" Raw string literal Declaring variable string back ticks: aString := `helllo, "DOG"`

Steps to tackle problems as Data Scientist: Formulate Question Not vague, be specific. Find the prediction (target/dependent variable), find what can correlate with the prediction, this will be the feature/independent variable. Gather Data Clean Data Explore/Visualize Data Train Algorithm Evaluate Results

Data Science: study of things related to data. Hierarchy = Collect -> Move/Store -> Explore/Transform -> Aggregate/Label -> Learn/Optimize Data Engineer, Collects and Move/Store Data Scientist, Explore/Transform and Aggregate/Label Machine Learning Expert, Use data to do ML

Convert one type to another type if there is a similar underlying type.     var xx int     var toddAge variableNameAge = 50     xx = int (toddAge)     fmt. Println (xx) Converted toddAge (type variableNameAge) to an int to be able to declare as xx which is type int.

Declaring a type: type variableNameAge int type variableNamePerson struct {} type variableNameDecimal float64 type variableNameName string type variableNameBig bool var toddAge variableNameAge = 50 var toddName variableNameName = "todd"

Packages need to be imported before use. Use: package main import "fmt" func main () {     fmt. Println ( "HELLO" ) } Packages are used in a program using the format PACKAGE.IDENTIFIER, fmt.Println(), fmt is PACKAGE, Println() is IDENTIFIER.

Go Module, allows easier use of dependencies and organization. - go mod init MODULENAME // creates a new go module using a domain name - go get -d PACKAGE // get package but do not build and install using d flag. Packages will be downloaded to GOPATH.

Go Workspace, workspace for packages, files for projects, etc. Separate from GO's installation root directory. Setup GO PATHS in environment variables (in system variables). GOROOT // points to Go root folder in C directory. GOPATH // points to the Go workspace folder Go workspace should be define in GO PATH. Go root directory defined by GO ROOT. Use go env to set workspace. Workspace requires: - bin - pkg - src

- go // lists go commands - go env // lists go environment variables - go env -w GOOS=linux // set go to compile to linux - go fmt // formats the go code into convention standard format. - go get // get packages from internet Compiling/Building Code/Packages: - go install //      For executables: builds/compiles the code and puts it in the GOPATH bin folder     For packages: builds/install the packages in GOPATH pkg folder - go build // builds the code as an executable in the current directory. - go clean // cleans residual build exes

Git Bash, emulator of shell bash for windows. Allows the use of Linux terminal commands. Git Bash included with Git as an exe. Escapes: - \ // backslash escapes spaces Key Shortcuts: - Tab // autocomplete Commands: - ./FILENAME // runs executable file - pwd // prints the working directory of where the terminal is in - ls // list files in the current working directory - ls -la // lists all files with extra details     First column is permissions for [owner, group, world] in rwxrwxrwx format.     the letter in front of rwxrwxrwx indicates whether its hidden, a directory, or windows (l) stuff - cd // change directory     - cd ../ // returns to parent directory - clear // clear the terminal - mkdir // creates a new directory - touch // create files - cat // read files, dumps content into terminal - nano // edit file? - grep // searches - rm // remove file     - rm -rf // remove with force - | // pipe, place after a command to use the output as another input into another command     - ls |