R Language
- Getting started with R Language
- Awesome Book
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- *apply family of functions (functionals)
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- data.table
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- Date-time classes (POSIXct and POSIXlt)
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- Regular Expression Syntax in R
- Regular Expressions (regex)
- Differences between Perl and POSIX regex
- Eliminating Whitespace
- Escaping characters in R regex patterns
- Validate a date in a "YYYYMMDD" format
- Validate US phone numbers
- Validate US States postal abbreviations
- Reproducible R
- Reshape using tidyr
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- The character class
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- tidyverse
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- Using texreg to export models in a paper-ready way
- Variables
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- Web scraping and parsing
- Writing functions in R
- xgboost
R Language Regular Expressions (regex) Validate US States postal abbreviations
Example
The following regex includes 50 states and also Commonwealth/Territory (see www.50states.com):
regex <- "(A[LKSZR])|(C[AOT])|(D[EC])|(F[ML])|(G[AU])|(HI)|(I[DLNA])|(K[SY])|(LA)|(M[EHDAINSOT])|(N[EVHJMYCD])|(MP)|(O[HKR])|(P[WAR])|(RI)|(S[CD])|(T[NX])|(UT)|(V[TIA])|(W[AVIY])"
For example:
> test <- c("AL", "AZ", "AR", "AJ", "AS", "DC", "FM", "GU","PW", "FL", "AJ", "AP")
> grepl(us.states.pattern, test)
[1] TRUE TRUE TRUE FALSE TRUE TRUE TRUE TRUE TRUE TRUE FALSE FALSE
>
Note:
If you want to verify only the 50 States, then we recommend to use the R-dataset: state.abb from state, for example:
> data(state)
> test %in% state.abb
[1] TRUE TRUE TRUE FALSE FALSE FALSE FALSE FALSE FALSE TRUE FALSE FALSE
We get TRUE only for 50-States abbreviations: AL, AZ, AR, FL.
