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False positive, False negative, Type I error, Type II error False positive, False negative, Type I error, Type II error True False True Correct Type II error False Type I error Correct Binary classification Actual Class Positive Actual Class Negative Assigned Positive True Positive False Positive Assigned Negative False Negative True Negative Statistics A positive result corresponds to rejecting the null hypothesis, while a negative result corresponds to failing to reject the null hypothesis; “false” means the conclusion drawn is incorrect. Thus a type I error is a false positive, and a type II error is a false negative. Wikipedia null hypothesis( H 0 ) H_0) H 0 ​ ) True null hypothesis( H 0 ) H_0) H 0 ​ ) False Fail to reject Correct (True Negative) (1- α \alpha α , confidence level) Type II error (False Negative) ( β \beta β ) Reject Type I error (False Positive) ( α \alpha α , signif...

inequalities Hoeffding’s Inequality Given n ( n > 0 ) n(n>0) n ( n > 0 ) i.i.d. random variables X 1 , X 2 , . . . , X n ∼ i i d X_1,X_2,...,X_n \overset{iid}{\sim} X 1 ​ , X 2 ​ , . . . , X n ​ ∼ i i d that are almost surely bounded – meaning P ( X ∉ [ a , b ] ) = 0 \mathbf{P}(X \notin [a,b])=0 P ( X ∈ / ​ [ a , b ] ) = 0 : P ( ∣ X n ˉ − E [ X ] ∣ ≥ ϵ ) ≤ 2 exp ⁡ ( − 2 n ϵ 2 ( b − a ) 2 ) for all  ϵ > 0 \mathbf{P}\left(\left| \bar{X_n} - \mathbb{E}[X]\right| \ge \epsilon\right) \le 2 \exp\left(-{2n\epsilon^2 \over (b-a)^2}\right) \qquad \text{for all }\epsilon \gt 0 P ( ∣ ∣ ​ X n ​ ˉ ​ − E [ X ] ∣ ∣ ​ ≥ ϵ ) ≤ 2 exp ( − ( b − a ) 2 2 n ϵ 2 ​ ) for all  ϵ > 0 Unlike for the central limit theorem, here the sample size n n n does not need to be large. Markov inequality For a random variable X ≥ 0 X\ge 0 X ≥ 0 with mean μ > 0 \mu \gt 0 μ > 0 , and any number t > 0 t \gt 0 t > 0 : P ( X ≥ t ) ≤...

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System hung whenever vscode was started. INSTALLING NVIDIA DRIVERS ON RHEL OR CENTOS 7( http://www.advancedclustering.com/act_kb/installing-nvidia-drivers-rhel-centos-7/ ). Somehow other parts were completed already, maybe nvidia package install script did that. Missing parts were 1. "blacklist nouveau" in /etc/pmodprobe.d/blacklist.conf 2. mv /boot/initramfs-$(uname -r).img /boot/initramfs-$(uname -r)-nouveau.img dracut /boot/initramfs-$(uname -r).img $(uname -r)

Command line tools 14 Command Line Tools to Check CPU Usage in Linux( https://linoxide.com/monitoring-2/10-tools-monitor-cpu-performance-usage-linux-command-line/ ) Understanding UNDERSTANDING CPU USAGE IN LINUX( https://www.opsdash.com/blog/cpu-usage-linux.html ) /proc filesystem can be used to access information directly.

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Install firebaseui-angular current firebaseui-angular 3.3.3 install spit out warnings with angular 7! Add the FirebaseUIModule with the config to your imports. CSS Import Import the firebaseui css to your src/styles.css file Use tag Use below tag where login select div is needed. ref :  https://www.npmjs.com/package/firebaseui-angular

ANGULARJS & MATERIAL AngularJS CLI New project. ng new projectname To use Angular Material npm install --save @angular/material @angular/cdk npm install --save @angular/animations include a polyfill . import {BrowserAnimationsModule} from '@angular/platform-browser/animations'; @NgModule({  ...  imports: [BrowserAnimationsModule],  ... }) export class PizzaPartyAppModule { } import the NgModule for each component you want to use import {MatButtonModule, MatCheckboxModule} from '@angular/material'; @NgModule({  imports: [MatButtonModule, MatCheckboxModule],  exports: [MatButtonModule, MatCheckboxModule], }) export class MyOwnCustomMaterialModule { } Include a theme style.css @import "~@angular/material/prebuilt-themes/indigo-pink.css"; Gesture Support npm install --save hammerjs After installing, import it on your app's entry point (e.g. src/main.ts). import 'hammerjs'; ...

File location : /usr/share/applications [Desktop Entry] Name=Sublime Text GenericName=Text Editor Comment=Edit source code Exec="path/to/sublime" %U Terminal=false Type=Application StartupNotify=true MimeType=text/plain; Icon="path/to/icon" Categories=TextEditor;Development;Utility;

The performance improvement from the use of generators is the result of the lazy (on demand) generation of values, which translates to lower memory usage. Furthermore, we do not need to wait until all the elements have been generated before we start to use them. This is similar to the benefits provided by iterators, but the generator makes building iterators easy from  https://wiki.python.org/moin/Generators Interesting thing!

2. Four identical dipole radiators are aligned parallel to one another and are equally spaced along a line at a distance apart. They are driven at a frequency of and are phased so that, starting from one end, each successive dipole lags the preceding one by . Find the intensity pattern of the radiation at a great distance in the equatorial plane (perpendicular to the dipole axes), and sketch this function in polar coordinates. Such a diagram is called the radiation pattern of an antenna system. My ans. At fixed point in equatorial plane with angle from dipole radiators aligned line, Let phase diff each adjacent dipole = : , where . first method Field, Using complex, Intensity, , substitue (1) Notice Above eq.(1) is valid when i.e. When , from orignal Intensity eq. second method just using eq.(30.3) substitue , graph x: red, y: green Initial intensity :1 Intensity scale : 1000 distance > 100 This could...

1. Two antennas are arranged as shown in Fig. 29-5(a) and are driven in phase. The antennas are driven so that one would, if alone, radiate a certain intensity in all horizontal directions, and the other, an intensity . What should the observed intensities in the various directions shown in the figure be? My ans. Intensity is proportional to square of the field. So, means . N, S phase diff = , N60, S60 using eq.(29.17) phase diff = using eq. (29.16) substitute, E, W in phase, This could be wrong.

1. Interpret the following two problems in complex numbers geometrically, and thus find absolute value of A in each case a) b) Ans a) b) Let radius of circle R(r in fig., but we have already r in problem. ), —-(1) —-(2) substitute (1) to (2)

Online books or notes Mathematical Tools for Physics The Poor Man’s Introduction to Tensors

Newtonian Dynamics by By Richard Fitzpatrick At UT Austin undergraduate senior level

Vector position vector Force vector Scalar triple product volume of parallel-piped defined by … Vector triple product BAC-CAB rule Differential Vector Operators irrotational solenoidal any gradient has a vanishing curl and is solenoidal any curl has a vanishing divergence and is irrotational vector Laplacian or Laplacian for Spherical coordinate Miscellaneous :scalar function, :vector function Del in cylindrical and spherical coordinates - wiki Vector Integration Integration by parts scalar function , vector function or vanish sufficiently strongly at infinity, i.e. integrated terms vanish at infinity

For fast convergence, it can be written without first term(i.e. 1) Using , bounds from integral test becomes, For six significant figures, at least , which gives where is negligible. So, six significant figures can be obtained from . , where bounds are check with simple javascript k= constant= ,bound{ }

For what values of p and q will converge? For sufficiently large independent of and , , so is dominant. , converges, so converges for all . , diverges(it’s harmonic numbers). But using integral test, , range of can be divided. converges. diverges. diverges. , diverges, so diverges for all .