Hello, Cyclus! [C++]

This pages walks you through a very simple hello world example using Cyclus agents. First make sure that you have the dependencies installed, namely Cyclus, CMake, and a recent version of Python (2.7 or 3.3+).

First, you need to get the cycstub code. Cycstub is a skeleton code base that you can use to quick-start new Cyclus module development projects. You can grab cycstub either by using git to clone the repository or by downloading the zip file. Let’s put this code in a tutorial directory and go into it.

Getting cycstub via git:

$ git clone https://github.com/cyclus/cycstub.git tutorial
$ cd tutorial

Getting cycstub via zip:

$ curl -L https://api.github.com/repos/cyclus/cycstub/zipball > tutorial.zip
$ unzip tutorial.zip
$ mv cyclus-cycstub-* tutorial
$ cd tutorial

---

Since cycstub is a template project everything is named stub. We need to change this to reflect the name we want our new project to be called - tutorial here. Cycstub comes with a renaming tool to do just this! From the command line, run Python in the following way:

tutorial $ python rename.py tutorial

---

Let’s now change the behavior of the TutorialFacility’s Tick() & Tock() member functions to print “Hello” and “World” respectively. To do this, please open up the src/tutorial_facility.cc file in your favorite text editor (vim, emacs, gedit, notepad++). Change the original functions to look like:

Original Tick() and Tock() in src/tutorial_facility.cc:

void TutorialFacility::Tick() {}

void TutorialFacility::Tock() {}

New Tick() and Tock() in src/tutorial_facility.cc:

void TutorialFacility::Tick() {std::cout << "Hello, ";}

void TutorialFacility::Tock() {std::cout << "World!\n";}

---

Now that we have altered the behavior of the TutorialFacility, let’s compile and install the tutorial project. This done with the install.py script. The install script puts the project into your cyclus userspace, ${HOME}/.local/lib/cyclus.

tutorial $ python install.py

---

Let’s run Cyclus with the TutorialFacility! In the input directory there is an example.xml. Running Cyclus on this file with the command cyclus input/example.xml should produce the following output.

tutorial $ cyclus input/example.xml
              :
          .CL:CC CC             _Q     _Q  _Q_Q    _Q    _Q              _Q
        CC;CCCCCCCC:C;         /_\)   /_\)/_/\\)  /_\)  /_\)            /_\)
        CCCCCCCCCCCCCl       __O|/O___O|/O_OO|/O__O|/O__O|/O____________O|/O__
     CCCCCCf     iCCCLCC     /////////////////////////////////////////////////
     iCCCt  ;;;;;.  CCCC
    CCCC  ;;;;;;;;;. CClL.                          c
   CCCC ,;;       ;;: CCCC  ;                   : CCCCi
    CCC ;;         ;;  CC   ;;:                CCC`   `C;
  lCCC ;;              CCCC  ;;;:             :CC .;;. C;   ;    :   ;  :;;
  CCCC ;.              CCCC    ;;;,           CC ;    ; Ci  ;    :   ;  :  ;
   iCC :;               CC       ;;;,        ;C ;       CC  ;    :   ; .
  CCCi ;;               CCC        ;;;.      .C ;       tf  ;    :   ;  ;.
  CCC  ;;               CCC          ;;;;;;; fC :       lC  ;    :   ;    ;:
   iCf ;;               CC         :;;:      tC ;       CC  ;    :   ;     ;
  fCCC :;              LCCf      ;;;:         LC :.  ,: C   ;    ;   ; ;   ;
  CCCC  ;;             CCCC    ;;;:           CCi `;;` CC.  ;;;; :;.;.  ; ,;
    CCl ;;             CC    ;;;;              CCC    CCL
   tCCC  ;;        ;; CCCL  ;;;                  tCCCCC.
    CCCC  ;;     :;; CCCCf  ;                     ,L
     lCCC   ;;;;;;  CCCL
     CCCCCC  :;;  fCCCCC
      . CCCC     CCCC .
       .CCCCCCCCCCCCCi
          iCCCCCLCf
           .  C. ,
              :
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!
Hello, World!

Status: Cyclus run successful!
Output location: cyclus.sqlite
Simulation ID: 0ae730e0-a9a8-4576-afaa-d1db6399d5a2

If you look in the input file you’ll see that the simulation duration was set to 10. This is why “Hello, World!” is printed ten times.