Author: blog

Unix shell

> echo "Hello, $LOGNAME"
Hello, Karl
> git clone https://github.com/*

Needs to remember the words like below
less, ls, pwd, mkdir, cat, curl, echo, git

console.log("hello!");
hello!

bash

Research

Brain Storm -> Create a Skelelon UI -> Research APIs and Libraries
Choose an Idea -> Create a paper prototype -> get user feedback -> Build APP

Developing nice graphic design
Building the user interface with UIKit
Downloading data from an API
Persisting the data
Working through problems and bug to get the app working well.
Posting the app to the App Store

-Create a Paper Prototype

Default Befaviors

Street Names
isStreetNamesEnabled()
setStreetNamesEnabled(boolean)
Zoom Gestures
isZoomGesturesEnabled
setZoomGesturesEnabled(boolean)
User Navigation
isUserNavigationEnabled
setUserNavigationEnabled(boolean)

@Override
public void onStreetViewPanoramaReady(StreetViewPanorama panorama){

	panorama.setPosition(new LatLng(37.400546,-112.108668));
	panorama.setStreetNamesEnabled(false);
	StreetViewPanoramaCamera camera = new StreetViewPanoramaCamera.Builder()
		.bearing(180)
		.build();
	panorama.animateTo(camera,1000);
}

User Interaction
Detect Camera Changes
setOnStreetViewPanoramaCameraChangeList
Detect User Touches on Panorama
setOnStreetViewPanoramaClickListener
Detect Changes to the Panorama
setOnStreetViewPanoramaChangeListener

Adding a Polyline

PolylineOptions().geodesic(true).add(LatLng);
PolylineOptions().geodesic(true).add(LatLng)
								.add(LatLng)
								.add(LatLng)
								.add(LatLng);

Use a streetViewPanoramaFragment

<fragment
	android:name="com.google.adroid.gms.maps.StreetViewPanoramaFragment"
	android:id="@+id/streetviewpanorama"
	android:layout_width="match_parent"
	android:layout_height="match_parent" />

StreetView Main Activity
Edit Activity
Implement OnStreetViewPanoramaReadyCallback
In OnCreate
Create a StreetViewPanoramaFragment Object
Call .getStreetViewPanoramaAsync(this) on it
Override onStreetViewPanoramaReady
Parameter: StreetViewPanorama
setPosition() for Location
Create a StreetViewPanoramaCamera
animate To(camera, ms)

@Override
prtected void onCreate(Bundle savedInstanceState){
 StreetViewPanoramaFragment StreetViewPanoramaFragment
  (StreetViewPanoramaFragment) getFragmentManager()
  	.findFragmentById(R.id.streetviewpanorama);

  	streetViewPanoramaFragment.getStreetViewPanoramaAsync(this);
 }

@Override
public void onStreetViewPanoramaReady(StreetViewPanorama panorama){

	panorama.setPosition(new LatLng(36.0579667,-112.1430996));
	StreetViewPanoramaCamera camera = new StreetViewPanoramaCamera.Builder()
		.bearing(180)
		.build();
	panorama.animateTo(camera,1000);
}

Using MarkerOptions

MarkerOptions class
position property takes a LatLng
title property takes a string

MarkerOptions renton =
	new MarkerOptions()
		.position(new LatLng(47.89805,-122.120502))
		.title("renton");
renton = new MarkerOptions()
	.position(new LatLng(47.48905, -122.120502))
	.title("Renton");
renton = new MarkerOptions()
	.position(new LatLng(47.48905, -122.120502))
	.title("Renton")
	.icon(BitmapDescriptorFactory.fromResource(
		R.drawable.ic_launcher));

Camera Position

Target, Zoom, Bearing, Tilt
class code: CameraPosition

CameraPosition cp=CameraPosition.builder()
	.target(LatLong)
	.zoom(val)
	.bearing(val)
	.tilt(val)
	.build();

	map.moveCamera(CameraUpdateFactory.newCameraPosition(cp));

	map.animateCamera(CameraUpdateFactory.newCameraPosition(cp),
		<time in ms>, <callback function>);

Making the map move
Seattle: 47.6204, -122.3491
New York: 40.7127, 74.0059
Dublin: 53,3478, 6.2597

Create and Configure the App

1. Create Blank Activity App
2. Edit build.grade
3. Edit Android.manifest
– meta for Google Service
– meta for API key
– permissions for internet, network state and write external storage
– meta for OpenGL

activity_main.xml

<fragment xmlns:android="http://schemas.android.com/apk/res/android"
	android:id="@+id/map"
	andorid:layout_width="match_parent"
	android:layout_height="match_parent"
	android:name="com.google.anroid.gms.maps.MapFragment"/>

Getting the SHA1 key for android

Find android Directory on computer
Then run Keytool command

~$ cd ~/ .android
.android$ keytool -list -v -keystore ~/.android/debug.keystore -alias androiddebugkey -storepass android -keypass android

Setting Up Maps
-set up billing
-create a project
-enable maps API
-set up credential

Google Developer Console
https://console.cloud.google.com/

Billing Account Steps
-Name the account
-Specify country for the Account
-Account Type: Business or Individual
-Payer Detail
-Payment Type

Pick Google Maps Android API “Enable”

MISE

Gaussian Kernel and Bandwidth
Mean Integrated Standard Error
E[|Pn-P|^2] = Ef(Pn(x)-P(x))^2*dx

We can technically use MISE or AMISE to select the Optimal Bandwidth

def MahalanobisDist(x, y):
	covariance_xy = np.cov(x,y, rowvar=0)
	inv_covariance_xy = np.linalg.inv(covariance_xy)
	xy_mean = np.mean(x),np.mean(y)
	x_diff = np.array([x_i - xy_mean[0] for x_i in x])
	y_diff = np.array([y_i - xy_mean[1] for y_i in y])
	diff_xy = np.transpose([x_diff, y_diff])
	md = []
	for i in range(len(diff_xy)):
		md.append(np.sqrt(np.dot(np.dot(np.transpose(diff_xy[i]), inv_covariance_xy),diff_xy[i])))
	return md

md = MahalanobisDist(x,xbar)

problem formulation => choice of los/ risk
purpose of the model => problem formulation

Identification
natural sciences, economics, medicine, some engineering

Prediction/Generalize
statistic/ machine learning, comple phenomenon, general applications

M
logistic regression, support vector machine, random forest

from sklearn.linear_model import LogisticRegression
from sklearn.svm import SVC
from sklearn.ensemble import RandomForestClassifier

def init_models(X_train, y_train):
	models = [LogisticRegression(),
			RandomForestClassifier(),
			SVC(probability=True)]

	for model in models:
		model.fit(X_train, y_train)

	return models

models = init_models(X_train, y_train)

Learning Curves
Plot of the model performance:
The Risk or Cost or Score vs.
Size of Training Set and Test Set
Classifiers: Score or l- Score

Kerndel Density Estimates

Non-Parametric Models: KDEs

Derived Feature: x = |f0 – f1|/f0
Definition: the ratio of the submitted charge to the difference between the submitted charge and payment amount by medicare.

x = abs(f0-f1)/f0
n0, bins0, patches0=plt.hist(x,100,normed=0,range=(0,1),histtype='stepfilled')
plt.setp(patches0, 'facecolor','g','alpha', 0.75)

from scipy import stats
from functools import partial
def my_kde_bandwidth(obj, fac=1./5):
	"""We use Scott's Rule, multiplied by a constant factor."""
	return np.power(obj.n, -1./(obj.d+4)) * fac

def getKDE(data, name="", bwfac = 0.2):
	x2 = data
	x_eval = np.linspace(x2.min() - 1, x2.max() + 1, 500)
	kde = stats.gaussian_kde(x2, bw_method=partial(my_kde_bandwidth, fac=bwfac))
	fig1 = plt.figure(figsize=(8.6))
	ax = fig1.add_subplot(111)
	plt.yscale=('log')
	plt.grid(True)
	x2h1, x2h2 = np.histogramix.bins=[0.,0.1,0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1.0],normed
	ax.plot(x2, np.zeros(x2.shape), 'b+', ms=12)