LaTeX : Part - 1 : Some Mathematical symbols, operators and many more related to Maths.

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How To: Create swap file in Ubuntu 11.04

1.       Open Terminal by pressing alt+ctrl+t
2.       Enter the command
               cat /proc/meminfo
3.       Now enter
                sudo dd if = /dev/zero of=/swapfile bs=1024 count=XX
                 swapfile size = count * bs
                e.g. count=2M  OR count = 2048K
                   so size=1024 * 2M = 2GB
4.       sudo chmod 600 /swapfile && sudo mkswap /swapfile
5.      sudo swapoff -a
6.      sudo swapon /swapfile
7.      sudo -b gedit /etc/fstab
                edit /etc/fstab file and remove or comment out all old swap partitions
8.       Add new line:
                /swapfile none swap sw 0 0
                verify that everything is done OK
9.     free -m
10.   Now you'll see your swap reported
                   swapon -s

How To : Enable/Disbale hibernate and suspend option in Ubuntu 11.04

Ubuntu Version 11.04

Steps:

1: Open terminal by pressing Alt+Ctrl+t

2: Enter the command given below

      

       sudo gedit /usr/share/polkit-1/actions/org.freedesktop.upower.policy 

   sudo command is used because the editing the file require root privilage and hence it requires password to enter.

3:  At the end suspend and hibernate section you will find two lines(if both are enabled):

       

      <allow_inactive>no</allow_inactive>
      <allow_active>yes</allow_active>

4:  Change yes to no and vice-versa. we assume that in your system both are enabled and you want to disabled it. If it is not the file contain the below lines

          <allow_inactive>yes</allow_inactive>
      <allow_active>no</allow_active>

 and now you have to turn "yes" to "no" and "no" to "yes" to make it enable.

Note : it's preferable to use "gksudo" instead of "sudo" when opening graphical programs, to prevent permission errors