Example#17(Array.Iter)

Posted by Rey Dacoco in

Problem: Make a console application that will convert the following singular nouns to plural. Use Array.Iter:

1. ally
2. army
3. baby
4. lady
5. navy

// Learn more about F# at http://fsharp.net
open System
//change the console title
System.Console.Title<-"Convert to Plural"
//adds the foreground and background color
System.Console.ForegroundColor<-ConsoleColor.Blue
System.Console.BackgroundColor<-ConsoleColor.White
//clears the screen. This is to apply the background color once the
//console application is loaded
System.Console.Clear()
//assigns the singular nouns to our array variable singularnouns
let singularnouns=[|"ally";"army";"baby";"lady";"navy"|]
printfn "Singular words:"
//iterates through the values of our singularnouns array variable
singularnouns|>Array.iter(fun singularwords->printfn "%s" singularwords)
printfn "Plural words:"
//iterates through the values of our singularnouns array variable
//replace the word in each array element from "y" to "ies"
singularnouns|>Array.iter(fun pluralnouns->
let pluralwords= pluralnouns.Replace("y","ies")
printfn "%s" pluralwords)

This will display the following output:

Visual F# 100 Examples: Example Number 16(Search a Record Value)

Posted by Rey Dacoco in

Problem: Make a Windows Forms Application that will allow the user to search a record value from a database file.

// Learn more about F# at http://fsharp.net
//specifies the memory location of the class files
//that will be needed in our application
open System.Collections.Generic
open System
open System.Windows.Forms
open System.ComponentModel
open System.Data
open System.Drawing
open System.Data.OleDb
//creates a font
let ffont=new Font("Verdana", 9.75F,FontStyle.Regular, GraphicsUnit.Point)  
//creates a connection object
let oleconn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;
  Data Source=C:\Documents and Settings\Station03\My Documents\dbEmployee.mdb")
 //creates an OleDbDataAdapter
let dataadpter = new System.Data.OleDb.OleDbDataAdapter("Select * from tblEmployee", oleconn)
//generates a dataset
let dataset11 = new DataSet()
//fills the dataset with recod values
dataadpter.Fill(dataset11,"tblEmployee")|>ignore
//creates a form
let dataform = new Form(Text="Search a Record Value",AutoScaleDimensions=new System.Drawing.SizeF(60.0F, 13.0F),ClientSize=new System.Drawing.Size(400, 360),StartPosition=FormStartPosition.CenterScreen)
//creates our controls
let exitbutton=new Button(Text="Exit", Location=new System.Drawing.Point(300, 320)) 
let searchbutton=new Button(Text="Search", Location=new System.Drawing.Point(220, 320))  
let label1=new Label(Text="Enter the employee number:",Location=new System.Drawing.Point(0, 10),AutoSize=true)
let label2=new Label(Text="Empno:",Location=new System.Drawing.Point(0, 50),AutoSize=true)
let label3=new Label(Text="Firstname:",Location=new System.Drawing.Point(0,100),AutoSize=true)
let label4=new Label(Text="Lastname:",Location=new System.Drawing.Point(0,150),AutoSize=true)
let empnotext=new TextBox(Location=new System.Drawing.Point(200,10))
let emplabel=new Label(Location=new System.Drawing.Point(100,50),BorderStyle=BorderStyle.FixedSingle)
let fnamelabel=new Label(Location=new System.Drawing.Point(100,100),BorderStyle=BorderStyle.FixedSingle)
let lnamelabel=new Label(Location=new System.Drawing.Point(100,150),BorderStyle=BorderStyle.FixedSingle)
//creates a datagrid
let datagrid = new DataGridView(ColumnHeadersHeightSizeMode=DataGridViewColumnHeadersHeightSizeMode.AutoSize,Size=new System.Drawing.Size(300, 120),Location=new System.Drawing.Point(10, 180))
//creates a grid control colums
let chrempnocol=new DataGridViewTextBoxColumn()
let chrfnamecol=new DataGridViewTextBoxColumn()
let chrlnamecol=new DataGridViewTextBoxColumn()
//adds the columns into our datagrid
datagrid.Columns.Add(chrempnocol)|>ignore
datagrid.Columns.Add(chrfnamecol)|>ignore
datagrid.Columns.Add(chrlnamecol)|>ignore
datagrid.DataSource <- dataset11.Tables.["tblEmployee"]
//assingns the font to our form
dataform.Font<-ffont
//links our fieldname to each grid
//and change its header text
chrempnocol.DataPropertyName<-"chrempno"
chrempnocol.HeaderText<-"Employee No."
chrfnamecol.DataPropertyName<-"chrfname"
chrfnamecol.HeaderText<-"First Name"
chrlnamecol.DataPropertyName<-"chrlname"
chrlnamecol.HeaderText<-"Last Name"
//add the datagrid to our form
dataform.Controls.Add(datagrid)
//adds the controls to our form
dataform.Controls.Add(exitbutton)
dataform.Controls.Add(searchbutton)
dataform.Controls.Add(label1)
dataform.Controls.Add(label2)
dataform.Controls.Add(label3)
dataform.Controls.Add(label4)
dataform.Controls.Add(empnotext)
dataform.Controls.Add(emplabel)
dataform.Controls.Add(fnamelabel)
dataform.Controls.Add(lnamelabel)
//binds the fieldnames to our label
emplabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(0).Item(0))
fnamelabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(0).Item(1))
lnamelabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(0).Item(2))
searchbutton.Click.Add(fun search->  
                    //handles the row index number               
                    let mutable introws=0
                    //determines if the record has been found or not
                    let mutable blnfound=false   
                    //handles the total number of records                
                    let mutable inttotrec=Convert.ToInt32(dataset11.Tables.["tblEmployee"].Rows.Count)
                    //handles the data inputted by the user
                    let strtext=Convert.ToString(empnotext.Text)
                    //while no match is found and the end of the file has not been reached
                    while((blnfound=false) && (introws<=inttotrec-1)) do
                         let strempnum=Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(introws).Item(0))
                         //compare the data inputted in the textbox to the employee number in our table
                         //if they are equal, display the match record
                         if strtext.ToUpper()=strempnum.ToUpper() then
                            blnfound<-true
                            emplabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(introws).Item(0))
                            fnamelabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(introws).Item(1))
                            lnamelabel.Text<-Convert.ToString(dataset11.Tables.["tblEmployee"].Rows.Item(introws).Item(2)) 
                         //compare to the next record while no match is found
                         introws<-introws + 1    
                    //if no match is found, display this      
                    if blnfound=false then
                        MessageBox.Show("Record not found.","Search a Record Value",MessageBoxButtons.OK,MessageBoxIcon.Information)|>ignore)                       
//when the exit button is clicked
exitbutton.Click.Add(fun exit->
//close the form and dataconnection
                    dataform.Close()
                    oleconn.Close()) 
//executes our application
Application.Run(dataform)

Since Visual F# is very particular with the code indention, I posted below the screenshot of our code in the while loop section.



Here's what it should look like if you click the run icon:

Visual F# 100 Examples: Example 14 and 15(Pattern Matching)

Posted by Rey Dacoco in

Pattern matching/match with statement is similar to the switch selection statement in other programming languages. The following examples demonstrate how to use it:


Problem: Make an application that will asks a letter and displays its equivalent U. S. military phonetic alphabet.

//use F# library
open System
//change the CLI title
System.Console.Title<-"Display Military Phoenitic Alphabet"
//adds color to our console application
System.Console.ForegroundColor<-ConsoleColor.Blue
//asks the user to enter a letter
printfn "Enter a letter:"
//convert the input to character and convert it to uppercase letter
//this is just for comparison purpose
let chrletter=Char.ToUpper(Convert.ToChar(System.Console.ReadLine()))
//clear the screen   
System.Console.Clear()
//match the value of chrletter to the ff. values
match chrletter with
//if the value of chrletter is a or A display Alpha
| 'A' ->printfn "Alpha"
//if the value of chrletter is b or B display Bravo
| 'B' ->printfn "Bravo"
//if the value of chrletter is c or C display Charlie
| 'C' ->printfn "Charlie"
//if the value of chrletter is d or D display Delta
| 'D' ->printfn "Delta"
//if the value of chrletter is e or E display Echo
| 'E'->printfn "Echo"
//if the value of chrletter is f or F display Foxtrot
| 'F'->printfn "FoxTrot"
//if the value of chrletter is g or G display Golf
| 'G'->printfn "Golf"
//if the value of chrletter is h or H display Hotel
| 'H'->printfn "Hotel"
//if the value of chrletter is i or I display India
| 'I'->printfn "India"
//if the value of chrletter is j or J display Juliet
| 'J'->printfn "Juliet"
//if the value of chrletter is k or K display Kilo
| 'K'->printfn "Kilo"
//if the value of chrletter is l or L display Lima
| 'L'->printfn "Lima"
//if the value of chrletter m or M display Mike
| 'M'->printfn "Mike"
//if the value of chrletter is n or N display November
| 'N'->printfn "November"
//if the value of chrletter is o or O display Oscar
| 'O'->printfn "Oscar"
//if the value of chrletter is p or P display Papa
| 'P'->printfn "Papa"
//if the value of chrletter is q or Q display Quebec
| 'Q'->printfn "Quebec"
//if the value of chrletter is r or R display Romeo
| 'R'->printfn "Romeo"
//if the value of chrletter is s or S display Sierra
| 'S'->printfn "Sierra"
//if the value of chrletter is t or T display Tango
| 'T'->printfn "Tango"
//if the value of chrletter is u or U display Uniform
| 'U'->printfn "Uniform"
//if the value of chrletter is v or V display Victor
| 'V'->printfn "Victor"
//if the value of chrletter is w or W display Whiskey
| 'W'->printfn "Whiskey"
//if the value of chrletter is x or X display X-Ray
| 'X'->printfn "X-Ray"
//if the value of chrletter is y or Y display Yankee
| 'Y'->printfn "Yankee"
//if the value of chrletter is z or Z display Zulu
| 'Z'->printfn "Zulu"
//otherwise
| _ ->printfn "Invalid input"
The last statement |_ is similar to the
default statement in other programming languages Switch conditional structure. It is automatically executed when no pattern match is found. Don't forget to add it at the end of every match with statement otherwise you will get an “Incomplete pattern matches on this expression” error.


Problem: Make an application that will ask the month number and display the corresponding month name and the number of days in it. Use pattern matching.

//use F# library
open System
//change the CLI title
System.Console.Title<-"Display Month Name"
//adds color to our console application
System.Console.ForegroundColor<-ConsoleColor.Blue
System.Console.BackgroundColor<-ConsoleColor.White
//asks the user to enter a month number
printfn "Enter a month number(1-12):"
let intmonth=Convert.ToInt32(System.Console.ReadLine())
//clear the screen   
System.Console.Clear()
//match the value of intmonth to the ff. values
match intmonth with
//if the value of intmonth is 1 display January
| 1 ->printfn "January(31 days)"
//if the value of intmonth is 2 display February
| 2 ->printfn "Febrary(28/29 days)"
//if the value of intmonth is 3 display March 
| 3 ->printfn "March(31 days)"
//if the value of intmonth is 4 display April
| 4 ->printfn "April(30 days)"
//if the value of intmonth is 5 display May
| 5 ->printfn "May(31 days)"
//if the value of intmonth is 6 display June
| 6 ->printfn "June(30 days)"
//if the value of intmonth is 7 display July
| 7 ->printfn "July(31 days)"
//if the value of intmonth is 8 display August
| 8 ->printfn "August(31 days)"
//if the value of intmonth is 9 display September
| 9 ->printfn "September(30 days)"
//if the value of intmonth is 10 display October
| 10 ->printfn "October(31 days)"
//if the value of intmonth is 11 display November
| 11 ->printfn "November(30 days)"
//if the value of intmonth is 12 display December
| 12->printfn "December(31 days)"
//otherwise
| _ ->printfn "Invalid input"

That's all for now my Visual F# friends. Ciao!

Visual F# 100 Examples: Example 12 and 13

Posted by Rey Dacoco in

This is the continuation of our planned 100 Visual F# examples. By the way, the bugs in examples number 7 to 11 had been fixed. My apologies, I should’nt have written those without using Visual F# compiler:)


Problem: Make a console application that will asks the user to enter the day that he was born and display his character or future based on the famous nursery rhyme written in England, “Monday’s Child”.

open System
//changes the console application title
System.Console.Title<-"Tell the Future"
//adds foreground color
System.Console.ForegroundColor<-ConsoleColor.Cyan
printfn "What day were you born?"
let strday=System.Console.ReadLine()
//clears the screen
System.Console.Clear()
//converts the inputs to lowercase then compare it our
//specified values
if strday.ToLower()="monday" then
    printfn "Monday's child is fair of face"
else if strday.ToLower()="tuesday" then
    printfn "Tuesday's child is full of grace"
else if strday.ToLower()="wednesday" then
    printfn "Wednesday's child is full of woe"
else if strday.ToLower()="thursday" then
    printfn "Thurdays's child has far to go"
else if strday.ToLower()="friday" then
    printfn "Friday's child is loving and giving"
else if strday.ToLower()="saturday" then
    printfn "Saturday's child works hard for a living"
else if strday.ToLower()="sunday" then
    printfn "Sunday's child is bonny and blithe and good and gay"
else
    printfn "Invalid input"
Problem: Develop a console application that will asks the wind speed in kilometer per hour(kph) and display its equivalent Philippine Storm Signal number.
open System
//changes the console application title
System.Console.Title<-"Determine Storm Signal Number"
//adds foreground color
System.Console.ForegroundColor<-ConsoleColor.Cyan
printfn "Enter wind speed(kph):"
let intspeed=Convert.ToInt32(System.Console.ReadLine())
//clears the screen
System.Console.Clear()
//if the wind speed ranges from 30 to 60
if intspeed>=30 && intspeed<=60 then
    printfn "Storm signal number 1"
//if the wind speed ranges from 61 to 100
else if intspeed>60 && intspeed<=100 then
    printfn "Storm signal number 2"
//if the wind speed ranges from 101 to 185
else if intspeed>100 && intspeed<=185 then
    printfn "Storm signal number 3"
//if the wind speed is greater than 185
else if intspeed>185 then
printfn "Storm signal number 4"
else 
printfn "Invalid input"

Visual F# 100 Examples: Example 11

Posted by Rey Dacoco in

Problem: Make a simple crack the treasure chest console application game.

// Learn more about F# at http://fsharp.net

open System
//change the title to Crack the Safe
System.Console.Title<-"Crack the Safe"
//change the foreground color to green
Console.ForegroundColor<-ConsoleColor.Green
//dislay the game title screen
printfn "\t\t\t Crack the Safe"
printfn "\t\t\t Press enter to continue..."
//waits for a keypress from the user
System.Console.ReadLine()|>ignore
//Game action sequence
printfn "\t\t\t You have found a legendary treasure chest"
printfn "\t\t\t believed to contain the rarest gem on Earth"
printfn "\t\t\t Press enter to continue... "
//waits for a keypress from the user
System.Console.ReadLine()|>ignore

printfn "\t\t\t this chest can be opened only by"
printfn "\t\t\t entering a mysterious 4-digit key code"
printfn "\t\t\t Press enter to continue..."
//waits for a keypress from the user
System.Console.ReadLine()|>ignore

let random=new Random()
let intkeycode=Convert.ToInt32(random.Next(1000,9999))

printfn "\t\t\tEnter the keycode:"
let intusercode= Convert.ToInt32(Console.ReadLine())
//if usercode is equal to the computer generated code then
if intusercode=intkeycode then
//display a congratulatory message
    printfn "\t\t\Congrats You have opened the treasure chest."

//otherwise 
else
    printfn "\t\t\tInvalid Code"

printfn "\t\t\tPress enter to continue... "
System.Console.ReadLine()|>ignore
printfn "\t\t\tGame Over"

Visual F# 100 Examples: Example 8 to 10

Posted by Rey Dacoco in

Problem: Make a console application that will accept five numbers and display the sum.

open System
//change the title to Add Five Numbers
System.Console.Title<-"Add Five Numbers "
//change the foreground color to cyan
Console.ForegroundColor<-ConsoleColor.Cyan
printfn "\t\t\tEnter the first number:"
let intnum1=Convert.ToInt32(System.Console.ReadLine())
printfn "\t\t\tEnter the second number:"
let intnum2=Convert.ToInt32(System.Console.ReadLine())
printfn "\t\t\tEnter the third number:"
let intnum3=Convert.ToInt32(System.Console.ReadLine())
printfn "\t\t\tEnter the fourth number:"
let intnum4=Convert.ToInt32(System.Console.ReadLine())
printfn "\t\t\tEnter the fifth number:"
let intnum5=Convert.ToInt32(System.Console.ReadLine())
let  intsum=intnum1+ intnum2 + intnum3 + intnum4 + intnum5
printfn "\t\t\tThe sum is:%i" intsum

Problem: Make a console application that will ask the power transmitted and power received then display the power loss value.
open System
//change the title to Calculate Power Loss
System.Console.Title<-"Calculate Power Loss "
//change the foreground color to cyan
Console.ForegroundColor<-ConsoleColor.Cyan
printfn "\t\t\t\tPower transmitted:"
let dblpowertrans=Convert.ToDouble(System.Console.ReadLine())
printfn "\t\t\tPower recieved:"
let dblpowerrec=Convert.ToDouble(System.Console.ReadLine())
let dblpowerloss= dblpowertrans/ dblpowerrec
printfn "\t\t\t Power loss:%f " dblpowerloss

Problem: Develop a console application that will ask the base value and height value then display the volume of a pyramid.
open System
//change the title to Volume of a Pyramid
System.Console.Title<-" Volume of a Pyramid"
//change the foreground color to cyan
Console.ForegroundColor<-ConsoleColor.Cyan
printfn "\t\t\tBase value:"
let dblbase=Convert.ToDouble(System.Console.ReadLine())
printfn "\t\t\tHeight value:"
let dblheight=Convert.ToDouble(System.Console.ReadLine())
let  dblvolume=(dblbase*dblheight)/3.0
printfn "\t\t\tVolume of a pyramid:%f" dblvolume

Visual F# 100 Examples: Example Number 7

Posted by Rey Dacoco in

So far I have been sharing to you guys some examples of Window Based application in Visual F#. This time, for variation sake lets make some console application:

Problem: Make a simple console application mind reader game.

open System
//change the title to Simple Mind Reader Game
System.Console.Title<-"Simple Mind Reader Game"
//change the foreground color to cyan
Console.ForegroundColor<-ConsoleColor.Cyan
//dislay the game title screen
printfn "\t\t\t Mind Reader Game"
printfn "\t\t\tPress enter to continue..."
//waits for a keypress from the user
System.Console.ReadLine()|>ignore
System.Console.Clear()
//the following does the game action sequence
printfn "\t\t\t Think of a five-digit number that has five unique numbers(Eg. 12345)"
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\t Reverse the numbers then subtract the smaller number from the larger number(Eg.54321- 12345)"
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\t Add 10000 to the difference"
printfn "\t\t\t Press enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\tVisualize the sum while I try to read your mind."
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\tThe sum is…"
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\tThe sum is…"
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\tThe sum is…"
printfn "\t\t\tPress enter to continue..."
System.Console.ReadLine()|>ignore
System.Console.Clear()

printfn "\t\t\t51976"

Contributor

My photo
I am just a simple man with a simple mind. And this is my simple blog. New Posts will be available soon. Enjoy reading and never stop learning:)

Total Pageviews

Link List

Archives

Got questions? You can reach me here: