Category: Examples

Examples, JavaScript, Node.js, Node.js Example

Get Latest CSV file from Folder using Node.js

by Dheeraj Kumar February 21, 2020 No Comments

getLatestFile.js



/***
 * Read lestest file property 
 * 
 */

const fs = require('fs')
async function getLatestFile() {
    const dirPath = '/home/dheeraj/Documents/BlogPost/Downloads';
    let dirCont = fs.readdirSync(dirPath);
    let files = dirCont.filter(function (elm) { return elm.match(/.*\.(csv)/ig); });
    for (let fileP = 0; fileP < files.length; fileP++) {
        let filsStats = fs.statSync(dirPath + "/" + files[fileP]);
        if (new Date(filsStats['birthtime']).getDate() === new Date().getDate() &&
            new Date(filsStats['birthtime']).getMonth() === new Date().getMonth() &&
            new Date(filsStats['birthtime']).getFullYear() === new Date().getFullYear() &&
            new Date(filsStats['birthtime']).getHours() === new Date().getHours() //&& 
        ) {
            return {
                fileName: files[fileP],
                fileLocation: dirPath + "/" + files[fileP]
            };
        }
    }
    return {
        fileName: 'orderFailed.png',
        fileLocation: dirPath + "/" + 'orderFailed.png'
    };
}

Generate test case
getLatestFile.test.js


const {getLatestFile} = require('./getLatestFile')

async function getLatest (){
    let latest = await getLatestFile();
     console.log(latest);
}

getLatest();

OutPut:

Download Code From git Repo

Data Analyst, Data Science, Data Visualization, Examples, R Language

Data visualization Examples in R

by Dheeraj Kumar February 20, 2020 No Comments

In this post, We will explore more examples of Data Visualization using R. For that purpose we are using mtcars as dataset
here is a list of all the features of the observations in mtcars:

  • mpg — Miles/(US) gallon
  • cyl — Number of cylinders
  • disp — Displacement (cu.in.)
  • hp — Gross horsepower
  • drat — Rear axle ratio
  • wt — Weight (lb/1000)
  • qsec — 1/4 mile time
  • vs — V/S engine.
  • am — Transmission (0 = automatic, 1 = manual)
  • gear — Number of forward gears
  • carb — Number of carburetors

Example 1: Plot graph on X and Y axis


# include ggplot2 library
library(ggplot2)

# 1 - Map mpg to x and cyl to y
ggplot(mtcars, aes(x=mpg, y=cyl)) +
  geom_point()

# 2 - Reverse: Map cyl to x and mpg to y
ggplot(mtcars, aes(x=cyl, y=mpg)) +
  geom_point()

OutPut:

Example 2: Change the color, shape, and size of the points


# include ggplot2 library
library(ggplot2)

#chnage color,shape and Size
ggplot(mtcars, aes(x=wt, y=mpg, col=cyl)) +
  geom_point(shape=1, size=4)

OutPut:

Example 3: Add alpha and fill


# include ggplot2 library
library(ggplot2)
# Expand to draw points with alpha 0.5 and fill cyl
ggplot(mtcars, aes(x = wt, y = mpg, fill = cyl)) +geom_point(alpha=0.5)

OutPut:

Exercise 4: Change Shape and color


library(ggplot2)
# Change shape and color
ggplot(mtcars, aes(x = wt, y = mpg, fill = cyl)) +geom_point(shape=24,col="yellow")

OutPut:

Exercise 5: Change shape and Size


# include ggplot2 library
library(ggplot2)
# Define a hexadecimal color
change_color <- "#4ABEFF"
# Set the fill aesthetic; color, size and shape attributes
ggplot(mtcars,aes(x=wt,y=mpg,fill=cyl))+ geom_point(size=10,shape=23,col=change_color)

OutPut: