sudo apt install php5=5.5.9+dfsg-1ubuntu4.20 php5-xdebug=2.2.3-2build1

https://askubuntu.com/questions/856996/cant-install-xdebug-depends-phpapi-20121212-ubuntu-14-04

Overall, the Lagrangian has units of energy, but no single expression for all physical systems. Any function which generates the correct equations of motion, in agreement with physical laws, can be taken as a Lagrangian. It is nevertheless possible to construct general expressions for large classes of applications. The non-relativistic Lagrangian for a system of particles can be defined by^[9]

where

is the total kinetic energy of the system, equalling the sum Σ of the kinetic energies of the particles,^[10] and V is the potential energy of the system.

Kinetic energy is the energy of the system’s motion, and v_k² = v_k · v_k is the magnitude squared of velocity, equivalent to the dot product of the velocity with itself. The kinetic energy is a function only of the velocities v_k, not the positions r_k nor time t, so T = T(v₁, v₂, …).

The potential energy of the system reflects the energy of interaction between the particles, i.e. how much energy any one particle will have due to all the others and other external influences. For conservative forces (e.g. Newtonian gravity), it is a function of the position vectors of the particles only, so V = V(r₁, r₂, …). For those non-conservative forces which can be derived from an appropriate potential (e.g. electromagnetic potential), the velocities will appear also, V = V(r₁, r₂, …, v₁, v₂, …). If there is some external field or external driving force changing with time, the potential will change with time, so most generally V = V(r₁, r₂, …, v₁, v₂, …, t).

https://en.wikipedia.org/wiki/Lagrangian_mechanics

File Operations

occ has three commands for managing files in ownCloud:

files
 files:cleanup              cleanup filecache
 files:scan                 rescan filesystem
 files:transfer-ownership   All files and folders are moved to another
                            user - shares are moved as well. (Added in 9.0)

The files:scan command scans for new files and updates the file cache. You may rescan all files, per-user, a space-delimited list of users, and limit the search path. If not using --quiet, statistics will be shown at the end of the scan:

sudo -u www-data php occ files:scan --help
  Usage:
  files:scan [-p|--path="..."] [-q|--quiet] [-v|vv|vvv --verbose] [--all]
  [user_id1] ... [user_idN]

Arguments:
  user_id               will rescan all files of the given user(s)

Options:
  --path                limit rescan to the user/path given
  --all                 will rescan all files of all known users
  --quiet               suppress any output
  --verbose             files and directories being processed are shown
                        additionally during scanning

Verbosity levels of -vv or -vvv are automatically reset to -v

When using the --path option, the path must consist of following components:

"user_id/files/path"
  or
"user_id/files/mount_name"
  or
"user_id/files/mount_name/path"

where the term files is mandatory.

Example:

--path="/alice/files/Music"

Source: Using the occ Command — ownCloud 9.0 Server Administration Manual 9.0 documentation

The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), associated with dark energy, and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos:

• the existence and structure of the cosmic microwave background
• the large-scale structure in the distribution of galaxies
• the abundances of hydrogen (including deuterium), helium, and lithium
• the accelerating expansion of the universe observed in the light from distant galaxies and supernovae

The model assumes that general relativity is the correct theory of gravity on cosmological scales. It emerged in the late 1990s as a concordance cosmology, after a period of time when disparate observed properties of the universe appeared mutually inconsistent, and there was no consensus on the makeup of the energy density of the universe.

The ΛCDM model can be extended by adding cosmological inflation, quintessence and other elements that are current areas of speculation and research in cosmology.

Some alternative models challenge the assumptions of the ΛCDM model. Examples of these are modified Newtonian dynamics, modified gravity, theories of large-scale variations in the matter density of the universe, and scale invariance of empty space.

https://en.wikipedia.org/wiki/Lambda-CDM_model

1) Keep the default zone apache.conf without the ScriptAlias.

2) Stop both zoneminder and apache2
sudo service apache2 stop
sudo service zoneminder stop

2) Remove any stale sockets from /tmp/zm (default location):
sudo rm -vf /tmp/zm/*.*

3) sudo a2enmod cgi

4) Start zoneminder
sudo service zoneminder start

5) Start apache2
sudo service apache2 start

I found out that the order was important for step 4 and 5, otherwise it doesn’t work

Source: Bug #1159361 “zoneminder not creating local unix sockets for str…” : Bugs : zoneminder package : Ubuntu

Install Zoneminder 1.30.4

Add Repository

NOTE:You may need to run: “apt install software-properties-common” if you did the minimal net install of Ubuntu.

add-apt-repository ppa:iconnor/zoneminder

Update Sources

apt update

Install Zoneminder

apt install zoneminder

Create a new user

adduser www-data video

Enable CGI, Zoneminder and rewrite configuration in Apache.

a2enmod cgi

a2enconf zoneminder

a2enmod rewrite

Fix Permissions

chown -R www-data:www-data /usr/share/zoneminder/

Enable and start Zoneminder

systemctl enable zoneminder

service zoneminder start

Add timezone to PHP

nano /etc/php/7.0/apache2/php.ini

Search for [Date] (Ctrl + w then type Date and press Enter) and make changes as follows for your time zone. Make sure to remove the ; from the front of date.timezone

[Date]
; Defines the default timezone used by the date functions
; http://php.net/date.timezone
date.timezone = America/New_York

Ctrl+o Enter to save

CTRL+x to exit

Restart Apache

service apache2 reload

IMPORTANT FINAL STEP: Open Zoneminder in a web browser (http://server-ip/zm). Click on Options – Paths and change PATH_ZMS to /zm/cgi-bin/nph-zms

Source: https://wiki.zoneminder.com/Ubuntu_Server_16.04_64-bit_with_Zoneminder_1.30.4_the_easy_way

You could simply disable it by:

sudo update-rc.d apache2 disable

and then if you would like to enable it again:

sudo update-rc.d apache2 enable

I had the same problem when I was handling multiple projects. I referred this article But it was like every time I need to switch the versions if need but this gives the flexibility for cli and web separately.

Moving From php5.6 to php7.0

For Apache, we can use the command as:

sudo a2dismod php5.6 ; sudo a2enmod php7.0 ; sudo service apache2 restart

For CLI, we can use the command as:

sudo update-alternatives --set php /usr/bin/php7.0

Moving From php7.0 to php5.6

For Apache, we can use the command as:

sudo a2dismod php7.0 ; sudo a2enmod php5.6 ; sudo service apache2 restart

For CLI, we can use the command as:

sudo update-alternatives --set php /usr/bin/php5.6

Source: server – How to have two versions of PHP installed and switch easily between them? – Ask Ubuntu

I figured out that on ubuntu 16.04 + gnome-shell, on the start up there is /usr/bin/gnome-keyring-daemon –start –components=ssh.

I figure out that removing –start –components=ssh was allowing to save the password, visible in the seahorse app

Source: ownCloud Sync client 1.5.3 for Linux won’t remember password · Issue #1590 · owncloud/client · GitHub

sudo apt-get install bum

Source: upstart – How to enable or disable services? – Ask Ubuntu

https://stackoverflow.com/questions/2837006/ob-start-and-ob-flush-doesnt-work