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szilard / meetup_raffle.R
Last active December 25, 2015 20:39
LA R meetup raffle
library(yaml)
library(RJSONIO)
library(httr)
event_id <- 132296372
n_max <- 20
api_key <- yaml.load_file("meetup_api_key.yml")$api_key
## get your api key from http://www.meetup.com/meetup_api/key/ while logged in
@szilard
szilard / sparse-linreg.R
Last active January 1, 2016 10:09
Sparse linear regression
library(Matrix)
rm(list=ls())
set.seed(123)
## parameters
n <- 1e6
library(RJSONIO)
library(httr)
library(ggplot2)
api_key <- scan("~/.meetup.apikey", character(), quiet = TRUE)
group_id <- 1414043 ## LA R meetup
req_url <- paste0("http://www.meetup.com/2/events?key=", api_key,
"&group_id=",group_id,"&status=past")
events_data <- fromJSON(rawToChar(GET(req_url)$content))$results
@szilard
szilard / rmarkdown-bug.Rmd
Created July 8, 2014 17:53
rmarkdown v2 bug report (submitButton does not delay in Embedded Shiny App)
---
runtime: shiny
output: html_document
---
```{r, echo=FALSE}
inputPanel(
selectInput("n", label = "n:", choices = c(10,50)),
submitButton("Update")
@szilard
szilard / dsla_raffle.R
Created August 9, 2014 08:01
DSLA raffles
library(dplyr)
read.csv("members_export.csv") %>%
mutate(pcrnk = percent_rank(CONFIRM_TIME), wdbl = ifelse(LinkedIn!="",2,1),
w = (3-2*pcrnk)*wdbl) %>%
sample_n(30, weight = w) %>%
mutate(name = paste(First.Name,Last.Name)) %>% select(name)
@szilard
szilard / min_benchm_datatable_pandas.R
Last active August 29, 2015 14:10
R data.table vs pandas aggregate/join
## Minimal example of R's data.table vs pandas aggregation and join benchmark
## ( more detailed but still basic benchmark here:
## http://datascience.la/dplyr-and-a-very-basic-benchmark/ )
## Just copy paste into R and Ipython, respectively
## Timings on a decent server with data.table 1.9.4 & pandas 0.15.1 (Nov 2014)
@szilard
szilard / shiny_sqlinj.R
Created January 7, 2015 06:57
shiny blog post on SQL injection
abbr <- input$inp_abbr
dbGetQuery(con, paste0("select * from states where abbr = '",abbr,"'"))
@szilard
szilard / shiny_sqlinj2.R
Created January 7, 2015 21:47
shiny blog post on SQL injection
abbr <- validinp_character(input$inp_abbr)
## or:
abbr <- validinp_character(input$inp_abbr, pattern="^((CA)|(NY))$")
@szilard
szilard / rf_subsamples.R
Last active August 29, 2015 14:19
Random Forest all data vs subsamples
library(randomForest)
library(parallel)
genr_data <- function(n,p) {
X <- matrix(rnorm(n*p),n,p)
y <- as.factor(apply(X,1, function(x)
ifelse(sum(x^2)>qchisq(0.5,p),"+","-")))
## Hastie etal 10.2
data.frame(X,y)
@szilard
szilard / rf_subsamples.py
Created April 15, 2015 22:31
Random Forest all data vs subsamples
import numpy as np
from scipy.stats import chi2
from sklearn.ensemble import RandomForestClassifier
n = 1000
p = 100
def genr_data(n,p):
X = np.random.randn(n,p)
y = np.zeros(n)