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stormxuwz / ts_seg.py
Created February 25, 2016 21:09
time series segmentation
import numpy as np
def slidingWindow(x,max_error):
n=len(x)
leftNode=0
segmentList=[]
print n
while leftNode<n-1:
print leftNode
@stormxuwz
stormxuwz / Google API.m
Created May 26, 2014 04:24
Matlab Google Street View and Direction API
origin='Madison,Chicago,IL';
destination='N+Michigan+Ave,Chicago,IL';
url1=['https://maps.googleapis.com/maps/api/directions/json?origin=' origin '&destination=' destination '&sensor=false&key= XXXX&departure_time=1343641500&mode=driving'];
direction=urlread(url1);
d=parse_json(direction);
steps=d{1}.routes{1}.legs{1}.steps;
[startpoints,endpoints]=cellfun(@parsecoord,steps);
@stormxuwz
stormxuwz / onlineClf.py
Created November 18, 2015 01:05
some online algorithm
from __future__ import division
import numpy as np
class OnlineClf(object):
def __init__(self,iterNum,R):
self.w=None
self.iterNum=iterNum
self.misNum=[[0,0]]
@stormxuwz
stormxuwz / three_dots.R
Created March 12, 2015 20:00
The three-dots construct in R
test_function_1 <- function(a=1){
cat("a is here",a)
}
test_function_2 <- function(b,...){
test_function_1(...)
}
test <- function(a,b){
test_function_2(b,a)
@stormxuwz
stormxuwz / VAR.py
Created February 25, 2015 06:30
Activity recognition by VAR model (HAR dataset)
import statsmodels.tsa as st
import numpy as np
import numpy.linalg as nl
import statsmodels.tsa as tsa
def solver_leastSquare(A,y):
return nl.lstsq(A,y);
def read_data(filename):
x=[]
@stormxuwz
stormxuwz / dft.py
Created February 2, 2015 05:21
This is a Discrete Fourier Transformation calculation using matrix mutiplication
def omega(N,k,n):
return np.exp(-2*np.pi/N*k*n*1j)
def hanWindow(N):
diag=np.array([np.sin(np.pi*i/(N-1))**2 for i in range(N)])
H=np.diag(diag)
return H
def createF(N):
F=np.zeros((N,N),dtype=complex)
@stormxuwz
stormxuwz / funcProb1.R
Created February 2, 2015 04:53
Some regression/classification in R
#### LDA,QDA, RDA, naive baye functions ####
lda.model=function(traindata){
lda.result=lda(Y~.,data=traindata)
return(lda.result)
}
lda.pred=function(model,dataSets.X){
predresult=lapply(dataSets.X,function(X) predict(model,X)$class)
errorInfo(predresult,"lda")
@stormxuwz
stormxuwz / GoogleAPI.py
Last active August 29, 2015 14:14
How to use Google Navigation and street view API and extract some features from a image
import urllib2;
import numpy as np;
import json;
from pyproj import Geod;
def decode_line(encoded):
"""copied from https://github.com/jconst/Byway-Server/blob/master/polyline.py
"""
encoded_len = len(encoded)
@stormxuwz
stormxuwz / Josephus_Problem
Created January 9, 2015 06:37
Josephus problem
# include <iostream>
using namespace std;
struct person{
person * previousPerson;
person * nextPerson;
int sword;
int num;
};
@stormxuwz
stormxuwz / boxplot_from_summary.R
Created October 24, 2014 16:41
box plot from summary
# http://stackoverflow.com/questions/10628847/geom-boxplot-with-precomputed-values
library(ggplot2)
DF <- data.frame(x=c("A","B"), min=c(1,2), low=c(2,3), mid=c(3,4), top=c(4,5), max=c(5,6))
ggplot(DF, aes(x=x, ymin = min, lower = low, middle = mid, upper = top, ymax = max)) +
geom_boxplot(stat = "identity")