Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • World
  • Users
  • Groups
Skins
  • Light
  • Cerulean
  • Cosmo
  • Flatly
  • Journal
  • Litera
  • Lumen
  • Lux
  • Materia
  • Minty
  • Morph
  • Pulse
  • Sandstone
  • Simplex
  • Sketchy
  • Spacelab
  • United
  • Yeti
  • Zephyr
  • Dark
  • Cyborg
  • Darkly
  • Quartz
  • Slate
  • Solar
  • Superhero
  • Vapor

  • Default (No Skin)
  • No Skin
Collapse
Code Project
  1. Home
  2. The Lounge
  3. The History of "i" [modified]

The History of "i" [modified]

Scheduled Pinned Locked Moved The Lounge
databasetutorialquestionloungelearning
56 Posts 37 Posters 0 Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • R Roger Wright

    In mathematics, i, j, and k are universal - they are used as integers, indices and to designate imaginary axes for vector quantities. This bled over into FORTRAN when computers were run almost exclusively for mathematicians and has stuck for decades. The use of n is a fairly new development, but it was only a matter of time before we ran out of integers. Fortunately, x and y are still usable for real numbers, and one has to grant them credit - there are an awful lot of real numbers. These valiant variables don't get half the credit they deserve... Engineers have done what we can to preserve the available pool of numeric variables. We use x, y, and z to designate unit vector directions, thereby reducing the load that i, j, and k have to carry. Recognizing the need to conserve, we have also adopted the variable s to designate the special value jw, mainly because it makes the math a lot easier. "...a photo album is like Life, but flat and stuck to pages." - Shog9

    J Offline
    J Offline
    Jorgen Sigvardsson
    wrote on last edited by
    #46

    Roger Wright wrote:

    The use of n is a fairly new development, but it was only a matter of time before we ran out of integers.

    You must be talking about Chuck Norris. He ran out of integers. Twice! :-D

    1 Reply Last reply
    0
    • M MatthysDT

      How does one discover a letter? :laugh::confused:

      L Offline
      L Offline
      Lilith C
      wrote on last edited by
      #47

      evilnoodle wrote:

      How does one discover a letter?

      I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was. Okay, so you don't discover letters, you create them. Reminds me though of an old George Carlin news report where he says that scientists had discovered a hitherto undiscovered new number between 6 and 7. It's "bleen'. Of course, he was thinking in terms of integers. But I had pictures in my head of a group of scientists who each had an extra appendage on their left hands. What I didn't look forward to was having to quote numbers like bleen thousand bleen hundred and bleenty-bleen. Lilith

      M D 2 Replies Last reply
      0
      • C code frog 0

        The possibilities are transcendental when you get David and Ryan going on Mathematics. Add in Chris and well... somehow it all equals "i" in the end...:laugh:


        The enemy's gate is down. :cool: Welcome to CP in your language. Post the unicode version in My CP Blog[^] now.

        C Offline
        C Offline
        CAReed
        wrote on last edited by
        #48

        I can't image that this conversation is even happening!!! Christopher Reed "The oxen are slow, but the earth is patient."

        1 Reply Last reply
        0
        • D David Stone

          Chris Maunder wrote:

          i is reserved for sqrt(-1)

          We're not going to start this discussion again...are we? :~

          They dress you up in white satin, And give you your very own pair of wings In August and Everything After

          I'm after everything

          P Offline
          P Offline
          Polymorpher
          wrote on last edited by
          #49

          just square it lol Pablo

          1 Reply Last reply
          0
          • A alex barylski

            You know the ubiqious "i" found in almost every example of a for loop for newbies? On another forum were having this disscussion (sorta)... I said (I believe I read it in an C K&R book) that it's because it's simply an alias for Index which is what "i" is usually doing in a for loop...?? Someone else says it has to do with: They are from general Summation Notation that, like many other mathmatical notations, worked its way into early languages -- specifically Fortran (remember its FORMula TRANSlation) I never would have guessed :P Cheers :) It's frustrating being a genius and living the life of a moron!!! -- modified at 21:18 Wednesday 4th October, 2006

            K Offline
            K Offline
            Ken R
            wrote on last edited by
            #50

            I'd look to the early definitions of Fortan (I think, it's too many languages ago now) which used the first letter of a variable to define the type (i, j, and k being the first 3 of the integer range). Of course you can bet that start point for integers came either from mathematical formula or being the first letter in the word integer, but I don't know. Happy hunting, Ken R.

            1 Reply Last reply
            0
            • F Francisco Viella

              Chris Maunder wrote:

              i is reserved for sqrt(-1)

              It depends. In electrical engineering, i is reserved for alternate current and, hence, we use j to refer to sqrt(-1). Francisco Silver at last!!

              A Offline
              A Offline
              aasales
              wrote on last edited by
              #51

              whereas the i in electrical engineering stands for current(DC and AC). But how did current symbol became i? Bec i is shortcut for the intensity of current per conductor cross area.

              1 Reply Last reply
              0
              • L Lilith C

                evilnoodle wrote:

                How does one discover a letter?

                I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was. Okay, so you don't discover letters, you create them. Reminds me though of an old George Carlin news report where he says that scientists had discovered a hitherto undiscovered new number between 6 and 7. It's "bleen'. Of course, he was thinking in terms of integers. But I had pictures in my head of a group of scientists who each had an extra appendage on their left hands. What I didn't look forward to was having to quote numbers like bleen thousand bleen hundred and bleenty-bleen. Lilith

                M Offline
                M Offline
                MatthysDT
                wrote on last edited by
                #52

                A number between 6 and 7. "The Nobel Prize in mathematics was awarded to a California professor who has discovered a new number! The number is bleen, which he claims belongs between 6 and 7." --George Carlin Seriously, this is like Guinness world records: "Please watch closely as this brave man attempts to set a new world record, that up until now didn't exist!" --- AWE.....AMAZING!!!!! you can't forget something you never knew...

                1 Reply Last reply
                0
                • L Lilith C

                  evilnoodle wrote:

                  How does one discover a letter?

                  I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was. Okay, so you don't discover letters, you create them. Reminds me though of an old George Carlin news report where he says that scientists had discovered a hitherto undiscovered new number between 6 and 7. It's "bleen'. Of course, he was thinking in terms of integers. But I had pictures in my head of a group of scientists who each had an extra appendage on their left hands. What I didn't look forward to was having to quote numbers like bleen thousand bleen hundred and bleenty-bleen. Lilith

                  D Offline
                  D Offline
                  Dan Neely
                  wrote on last edited by
                  #53

                  Lilith.C wrote:

                  I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was.

                  I thought it was the other way around. I'm remembering crucifixes marked INRI "Jesus of Nazareth king(Rex) of the Jews" from sundayschool.

                  L 1 Reply Last reply
                  0
                  • D Dan Neely

                    Lilith.C wrote:

                    I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was.

                    I thought it was the other way around. I'm remembering crucifixes marked INRI "Jesus of Nazareth king(Rex) of the Jews" from sundayschool.

                    L Offline
                    L Offline
                    Lilith C
                    wrote on last edited by
                    #54

                    dan neely wrote:

                    Lilith.C wrote: I don't remember the history other than reading it in a Heinlein novel, but I believe the story is that 'i' as a letter was added to the alphabet much later than most letters. Before that the letter 'j' was used where the 'i' was. I thought it was the other way around. I'm remembering crucifixes marked INRI "Jesus of Nazareth king(Rex) of the Jews" from sundayschool.

                    That could well be. As J sajd, J don't remember the hjstory that well. Ljljth

                    1 Reply Last reply
                    0
                    • A alex barylski

                      You know the ubiqious "i" found in almost every example of a for loop for newbies? On another forum were having this disscussion (sorta)... I said (I believe I read it in an C K&R book) that it's because it's simply an alias for Index which is what "i" is usually doing in a for loop...?? Someone else says it has to do with: They are from general Summation Notation that, like many other mathmatical notations, worked its way into early languages -- specifically Fortran (remember its FORMula TRANSlation) I never would have guessed :P Cheers :) It's frustrating being a genius and living the life of a moron!!! -- modified at 21:18 Wednesday 4th October, 2006

                      M Offline
                      M Offline
                      Micarl
                      wrote on last edited by
                      #55

                      The votes are in: The 'i's have it.

                      1 Reply Last reply
                      0
                      • C code frog 0

                        I think I reserved i for 2 people at 7:00. :doh:


                        The enemy's gate is down. :cool: Welcome to CP in your language. Post the unicode version in My CP Blog[^] now.

                        D Offline
                        D Offline
                        db_cooper1950
                        wrote on last edited by
                        #56

                        (i)bid to the (I)nteger:laugh: DB_Cooper1950

                        1 Reply Last reply
                        0
                        Reply
                        • Reply as topic
                        Log in to reply
                        • Oldest to Newest
                        • Newest to Oldest
                        • Most Votes


                        • Login

                        • Don't have an account? Register

                        • Login or register to search.
                        • First post
                          Last post
                        0
                        • Categories
                        • Recent
                        • Tags
                        • Popular
                        • World
                        • Users
                        • Groups