LaTeX/C2/Numbering-Equations/English-timed
From Script | Spoken-Tutorial
| Time | Narration |
| 00:01 | Welcome to this tutorial on numbering equations using LaTeX.
My name is Kannan Moudgalya. |
| 00:09 | In this tutorial, we will learn- |
| 00:12 | How to put equation numbers |
| 00:15 | How to remove them |
| 00:17 | How to correctly reference equations |
| 00:21 | How to use the information on the web |
| 00:25 | One may use any of Linux, Windows or a Mac operating system. |
| 00:31 | One needs LaTeX. |
| 00:34 | I shall use TeXworks. |
| 00:37 | What are the prerequisites? |
| 00:39 | One needs to be familiar with spoken tutorials that introduce LaTeX. |
| 00:45 | We recommend the use of the Side-by-Side method. |
| 00:49 | This information is available at the Spoken Tutorial webpage. |
| 00:55 | I shall use the following files: |
| 00:58 | numbers.tex, which you can see here. |
| 01:03 | ltxprimer pdf file from TUG India. It is here. |
| 01:09 | These are available as Code files along with this tutorial. |
| 01:14 | With these files, you will be able to practise along with me. |
| 01:19 | If you don't have these files, please download them from the Spoken Tutorial website. |
| 01:26 | Let us begin the tutorial. |
| 01:28 | Let us learn how to create numbers for equations in LaTeX. |
| 01:33 | I have already opened the file numbers.tex in TeXworks. |
| 01:39 | I have saved it as align.tex to use in this tutorial. |
| 01:44 | I will keep the numbers.tex file intact, and not change it. |
| 01:49 | Please pause the tutorial, make a copy of numbers.tex and open it. |
| 01:55 | Whenever you want to start afresh, you can make a new copy of numbers.tex |
| 02:01 | I recommend this method whenever a code file is given with ANY spoken tutorial. |
| 02:08 | Let me open align.tex |
| 02:11 | Let us compile this file by pressing the Typeset arrow at the top left hand corner. |
| 02:18 | You can see the pdf file on the right. |
| 02:22 | These equations do not have numbers. |
| 02:26 | We can put equation numbers by removing the star from the align star. |
| 02:32 | Let us remove the star from both begin and end statements. |
| 02:39 | Forgetting it in the end statement is a common mistake. |
| 02:43 | Let’s see what happens if I forget to remove it from the end align statement. |
| 02:49 | Let us compile. |
| 02:51 | It gives an error message begin align ended with align star. |
| 02:57 | Let us remove the star from end align also. |
| 03:02 | Let us abort typesetting and compile. |
| 03:07 | We now have equation numbers. |
| 03:11 | Let us now refer to the second equation in the running text. |
| 03:16 | Put the number 2 after the word equation. |
| 03:21 | Compile.
We see number 2 in the running text. |
| 03:27 | I will now show you how to remove the equation number of one equation. |
| 03:32 | Suppose that we don’t want a number for the first equation. |
| 03:37 | Go to the end of the first equation, but before intertext, and put back slash nonumber. |
| 03:46 | Please note that nonumber is one word. |
| 03:50 | Do not forget the back slash at the beginning. |
| 03:54 | On compiling, the number disappears from the first equation. |
| 04:00 | One consequence is that the second equation is now numbered as one. |
| 04:07 | Unfortunately, the reference to the second equation has become wrong in the text. |
| 04:13 | Can we prevent such mistakes even if we have to add or remove equations? |
| 04:19 | Such a requirement occurs frequently while writing reports, theses, papers, etc. |
| 04:27 | It is possible to do this through the label statement. |
| 04:32 | We have seen this in a previous tutorial also. |
| 04:36 | Let me put slash label PID at the end of the second equation, but before end align. |
| 04:47 | Replace 2 in the running text with slash ref PID as I do now. |
| 04:56 | After compiling once, two question marks appear against the equation number. |
| 05:02 | On compiling twice, the question marks get replaced by the correct number. |
| 05:09 | Let us change the equation number once again by removing nonumber. |
| 05:15 | Compile twice to get correct answers. |
| 05:20 | The variable in the ref and label commands have to be identical. |
| 05:26 | Check what happens if you change PID in the ref command to lowercase. |
| 05:34 | Leave the PID in uppercase in the label command and compile. |
| 05:40 | We get question mark here because this lowercase pid is not defined. |
| 05:48 | I will put pid back in uppercase and compile. |
| 05:55 | I will now show you how to take help from the Internet. |
| 06:00 | Before that, I am going to delete everything in the tex file. |
| 06:05 | If you don’t like it, you can open a new file. |
| 06:09 | To do this part, you need access to Internet.
If you don’t have this access now, you may try this part later. |
| 06:17 | Let me go to a web browser. |
| 06:20 | Let me do a web search on the topic of LaTeX multiline. |
| 06:27 | The very first hit is on stackexchange. |
| 06:32 | Let me click this “How to align...”. |
| 06:36 | If you scroll down this page, you will see a question and several answers. |
| 06:43 | Most answers present a complete code. |
| 06:48 | Let us copy the code that says 58. |
| 06:53 | This number may be different when you access this page. |
| 06:58 | Below this, the pdf file created by this code is shown. |
| 07:04 | Let me paste it on the tex file. |
| 07:08 | Let us compile the tex file. |
| 07:11 | You can check the output in this pdf file to be identical to what we saw in stackexchange. |
| 07:19 | Please try all commands explained in this web page and understand them. |
| 07:24 | Next let me delete everything inside the document environment. |
| 07:31 | Let us now open the ltxprimer pdf file that we have provided with this tutorial. |
| 07:38 | You can practise this part even if you don’t have web access. |
| 07:43 | Let us scroll and go to Contents. |
| 07:48 | Let us click “Typesetting Mathematics”. |
| 07:52 | You can see many examples. |
| 07:55 | Let us go to page 87. |
| 07:59 | Let us copy “cases code” and paste it within the document environment. |
| 08:08 | On compiling it, we get the output given in ltxprimer. |
| 08:14 | You may change equation* to align*, and compile. |
| 08:20 | We get identical results. |
| 08:23 | I suggest that you spend a minute in understanding this example. |
| 08:28 | I also suggest that you try more examples from ltxprimer. |
| 08:33 | This brings us to the end of this tutorial. |
| 08:37 | This page summarises what we learnt in this tutorial. |
| 08:42 | Please recall each of these commands.
This is your first assignment. |
| 08:48 | Please do a search on these commands over the web, in ltxprimer, etc.
Locate these examples and try them out. |
| 08:59 | I will give some more assignments. |
| 09:03 | We compiled twice to get correct numbers.
Why should we compile twice? |
| 09:09 | Hint: we saw this in an earlier tutorial. |
| 09:13 | You can also locate an answer for this in ltxprimer.pdf file. |
| 09:19 | Search for Cross References. |
| 09:22 | Try examples from Chapter 8 of ltxprimer pdf file we saw earlier.
Try to understand them. |
| 09:30 | Try multiline examples from the Stackexchange web page we saw earlier. |
| 09:36 | I will now give some general information. |
| 09:40 | This video summarises the Spoken Tutorial project. |
| 09:45 | We conduct workshops using Spoken Tutorials. |
| 09:50 | Do you have questions in THIS Spoken Tutorial? |
| 09:54 | Please visit this site |
| 09:56 | Choose the minute and second where you have the question |
| 10:00 | Explain your question briefly |
| 10:03 | Someone from our team will answer them |
| 10:06 | You will have to register on this website to ask questions. |
| 10:11 | For topics not covered in spoken tutorials, visit stackexchange at this address. |
| 10:17 | This is a great place to get answers on LaTeX. |
| 10:22 | You may also have questions on our workshops, certificates, etc.
For this, get in touch with us at this email address. |
| 10:32 | Spoken Tutorial project is funded by MHRD, Government of India. |
| 10:37 | Thanks for joining.
Goodbye. |
