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Last modified: 23 March 2022


Downloading CIAO 4.13 and CALDB 4.9.7

The download page provides the basic steps needed to install CIAO 4.13 and CALDB 4.9.7 into a new conda environment. For additional details, including how to upgrade an existing environment, users should read the Installing CIAO with conda thread.

Also be sure to review the list of known issues and conflicts with other packages on the conda installation bug page as well as the conda FAQs.

conda is the preferred method to install CIAO. Users looking to use the ciao-install script can skip to the bottom of this page.

  1. Please be aware of the following issues before installing CIAO 4.13 (see the watchout page for more information):

  2. Verify conda version. Users should be using conda version 4.7.6 or newer.

    $ conda --version
    conda 4.8.3

    If conda is not installed,

    $ conda --version
    conda: Command not found.

    users can install miniconda from the Anaconda website.

  3. Install CIAO into a new conda environment.

    $ conda create -n ciao-4.13 \
      -c \
      ciao sherpa ds9 ciao-contrib caldb_main marx

    Users may also wish to includes packages such as jupyter, astropy, and scipy into their new CIAO conda environment.

  4. Activate the CIAO environment

    tcsh% conda activate ciao-4.13
    bash$ source activate ciao-4.13

    By default, the terminal prompt will change to show the currently active conda environment. Users can also run the ciaover command to verify that they are setup correctly.

    (ciao-4.13)$ ciaover -v
    # packages in environment at /soft/miniconda/envs/ciao-4.13b2:
    # Name                    Version                   Build  Channel
    ciao                      4.13.0           py38h5ec60c1_2
    ciao-contrib              4.13.3                     py_0
    ds9                       8.2                           1
    sherpa                    4.13.0           py38h5ec60c1_2
    System information:
    Linux 3.10.0-1062.12.1.el7.x86_64 #1 SMP Tue Feb 4 23:02:59 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

    Users may want to create an alias so that they only need to type ciao to activate their environment.

  5. Run the CIAO smoke tests:
    $ cd $ASCDS_INSTALL/test
    $ make

    If there are any errors reported during the smoke tests, users can check the smoke test bugs page for possible solutions.

  6. Finished! CIAO is now installed and you can being your data reduction and analysis work.

conda is preferred installation method, ciao-install alternative

The CXC now suggests that users install CIAO using the conda package management system. This method allows users to more easily add 3rd party Python packages into their environment.

Alternatively, users can install CIAO using the ciao-install script. Follow this link for instructions:

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