Publications by IvanTikhonov
DATA608Module3
#Libraries required library(ggplot2) library(plotly) ## ## Attaching package: 'plotly' ## The following object is masked from 'package:ggplot2': ## ## last_plot ## The following object is masked from 'package:stats': ## ## filter ## The following object is masked from 'package:graphics': ## ## layout library(shiny) library...
1413 sym R (5743 sym/33 pcs)
DATA609 Module3
Write down Newton’s formula for finding the minimum of \[f(x) = \frac{(3x^{4} - 4x^{3})}{12}\] in the range of [-10,10]. Then, implement it in R. Let’s first visualize the curve: The blue line is f(x) and the red line is f′(x) f <- function(x){ (3*x^4 - 4*x^3)/(12) } f_prime <- function(x){ (x^3 - x^2) } curve(f, col = 'blue', xl...
3728 sym R (1242 sym/8 pcs) 1 img
DATA 621 HW 1
1. DATA EXPLORATION Overview The moneyball-training-data contains 17 columns(INDEX, TARGET_WINS, TEAM_BATTING_H, TEAM_BATTING_2B, TEAM_BATTING_3B, TEAM_BATTING_HR, TEAM_BATTING_BB, TEAM_BATTING_SO, TEAM_BASERUN_SB, TEAM_BASERUN_CS, TEAM_BATTING_HBP, TEAM_PITCHING_H, TEAM_PITCHING_HR, TEAM_PITCHING_BB, TEAM_PITCHING_SO, TEAM_FIELDING_E, TEAM_FI...
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DATA608module2
For module 2 we’ll be looking at techniques for dealing with big data. In particular binning strategies and the datashader library (which possibly proves we’ll never need to bin large data for visualization ever again.) To demonstrate these concepts we’ll be looking at the PLUTO dataset put out by New York City’s department of city plan...
3085 sym R (12972 sym/28 pcs)
DATA609Module2HW2
Ex.1 Show x2+exp(x)+2x4+1 is convex. f(αx+βy)≤αf(x)+βf(y) (αx+βy)2+exp(αx+βy)+2(αx+βy)4+1≤α(x2+exp(x)+2x4+1)+β(y2+exp(y)+2y4+1) Using α+β=1 we can simplify the inequality and rewrite it as 2αx4+αx2+αexp(x)+2βy4+βy2+βexp(y)+1−((αx+βy)2+exp(αx+βy)+2(αx+βy)4+1)≥0 2αx4+αx2+αexp(x)+2βy4+βy2+βexp(y)−(αx+βy)2�...
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DATA608-Module1
Principles of Data Visualization and Introduction to ggplot2 I have provided you with data about the 5,000 fastest growing companies in the US, as compiled by Inc. magazine. lets read this in: library(ggplot2) library(dplyr) ## ## Attaching package: 'dplyr' ## The following objects are masked from 'package:stats': ## ## filter, lag ...
1521 sym R (5973 sym/24 pcs) 8 img
DATA609-Module1HW
Ex.1 Find the minimum of f(x,y)=x²+xy+y²in(x,y)∈R². Solution: The stationary conditions are ∂f/∂x=2x+y=0 and ∂f/∂y=x+2y=0 From the second condition we get either x = -2y or y = −x/2 Substituting x = -2y into the first condition gives us 2(-2y) + y = 0 -4y + y = 0 -3y = 0 y = 0 Substituting y = −x/2 into the first condition gives ...
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IvanTikhonov 602 lab1
install.packages(“tidyverse”) install.packages(“openintro”) install.packages(“dplyr”) library(tidyverse) ## ── Attaching packages ─────────────────────────────────────── tidyverse 1.3.2 ── ## ✔ ggplot2 3.3.6 ✔ purrr 0.3.4 ## ✔ tibble...
2122 sym R (6356 sym/46 pcs) 6 img
IvanTikhonov 606lab2
library(tidyverse) ## ── Attaching packages ─────────────────────────────────────── tidyverse 1.3.2 ── ## ✔ ggplot2 3.3.6 ✔ purrr 0.3.4 ## ✔ tibble 3.1.8 ✔ dplyr 1.0.10 ## ✔ tidyr 1.2.0 ✔ stringr 1.4.0 ## ✔ readr 2.1.2...
4448 sym R (8125 sym/35 pcs) 8 img
605_Assignment_3
Problem set 1 What is the rank of the matrix A? | 1 2 3 4| A =| −1 0 1 3| | 0 1 −2 1| | 5 4 −2 −3| Convert A to RREF | 1 2 3 4| RREF | 1 0 0 0| A =| −1 0 1 3| ——> | 0 1 0 0| | 0 1 −2 1| | 0 0 1 0| | 5 4 −2 −3| | 0 0 0 1| rank is 4, there are no linear independent rows A = matrix(c(1,2,3,4,-1,0,1,3,0,1,-2,1,5,4,-2,-3), nrow=...
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